Skip to main content

Full text of "The Leica Manual A Manual For The Amateur And Professional Covering The Entire Field Of Leica Photography"

See other formats

ift.-.s.-a-         ..$A*°° I 

"  h  _i 

Keep  Your  Car  din  This  Pocket 

r  cards. 

•  Unless  labeled  otherwise,  books  may  be  retained 
for  two  weeks.  Borrowers  finding  books  marked,  de- 
faced or  mutilated  me  expected  to  report  g*»rv»  at 
library  desk;  otherwise  the  last  borrower  will  be  held 
responsible  for  all  imperfections  discovered. 

Tie  card  holder  is  responsible  for  all  books  drawn 
bnlhiscaid.  » 

Penalty  for  o^er-due  books  2o  a  day  plus  cost  of 

Lost  cards  and  change  of  residence  must  be  re- 
ported promptly . 

Public  Library 

Kansas  City,  Mo. 
Keep  Your  Card  in  This  Pocket 


0  000114510321  4 


H.    W.    ZIELER 
JOHN    T.    MOSS,    JR. 
A.    L.    LUGN 
JOHN    N.    HARMAN,    JR. 


A    Manual   for   the    Amateur    and   Professional 
Covering  the  Entire  Field  of  Leica  Photography. 


and  Contributors 


100  EAST  42ND  STREET,  NEW  YOHK  JiWV// 


Second  Edition  [ 

First  Printing  December  1936 

First'  'Printing/  August  1935  - 
Second  Prmtiiig'  ^p^  J535 
Third  Printing  August* 

Copyright  1936 

Willard  D.  Morgan 
Henry   M.   Lester 

,  -       r( 

All  rights  reserved  in  all  countries.  No  part  of  this  book 
may  be  reproduced  or  translated  in  any  form  without 
permission  in  writing  from  the  editors  and  publishers. 

Printed  in  0.S.A,  By  Wagner  Printing  Co.,  Inc.,  New  Y< 


The  Editors  wish  to  express  their  appreciation  to  all 
those  who  have  assisted  in  the  compilation  of  this  work : 


of  chapters,  and  the  many  friends  working  with  the 
miniature  camera  who  have  submitted  photographs  and 
helped  to  formulate  the  scope  of  this  Manual 

Barbara  Morgan 

for  planning  typographical  and  montage  arrangement 

Bnth  Lester 

for  collaboration  in  the  editing  of  the  volume. 


Before  We  Press  the  Button 7 

by  Manuel  Komroff 

An  Introduction  to  Leica  Photography 17 

by  Willard  D.  Morgan 

A  New  Camera  for  New  Interpretations.  Why  Specialized 


CHAPTER  1.    Leica  and  Its  Auxiliary  Equipment 23 

by  Willard  D.  Morgan 

What  to  Photograph  with  a  Leica.  Know  Your  Leica. 
Your  Beginning.  How  to  Make  Your  First  Leica  Picture* 
Models  F  and  G  Leicas.  Interior  Mechanism  of  the  Leica. 
Loading  the  Leica  Film  Magazine.  Earlier  Leica  Models. 
Leica  Accessories.  Vidom  Universal  View  Finder.  Wide 
Angle  View  Finder.  Direct  View  Finder.  Wintu  Angle 
Finder.  Sunshades  and  Their  Use.  Slow  Timing  Device. 
Rapid  Winder.  Protective  Cases.  Flashlight.  Single 
Exposure  Leica,  and  Film  Holder*  Summary. 

CHAPTER  2.    Leica  Lenses 49 

by  H.  W.  Zieler 

The  Iris  Diaphragm.  The  Miniature  vs.  Larger  Cameras. 
Depth  of  Focus  and  Eelative  Aperture.  Depth  of  Focus 
scale.  Exposure  Variations.  Perspective  and  the  Various 
Leica  Lenses.  The  50mm  Lenses.  Other  Leica  Lenses. 
Proper  Care  of  Lenses.  Front  Lenses. 

CHAPTER  3.    Color  Filters 81 

by  Henry  M.  Lester  and  Karl  A,  Barleben,  Jr. 

When  Filters  Should  be  Used.  Color  Sensitivity  Charts. 
Color  Balance  correction  of  Contrast.  Making  Your  Own 
Filter  Tests.  Filter  Factors.  Choice  of  Film  and  Filter. 
What  Filters  to  Use.  Filter  Factor  Table. 

CHAPTER  4,     The  35mm  Film— Its  Selection,  Exposure. 

and  Development __..__  97 

by  Henry  M.  Lester 

Part  I —  Film  Selection 

Sensitivity  to  Color.  Speed  of  Emulsion.  Graininess. 
Contrast.  Latitude.  Panchromatic  Emulsions.  Ortho- 
chromatic,  Special,  and  Color-Blind  Emulsions.  Reversi- 
ble and  Infra-Red  Films.  When  to  Use  a  Certain  Film. 

Part  II  —  Film  Exposure 

Exposure  Meters.  How  to  Use  an  Exposure  Meter.  Ex- 
posures Without  a  Meter.  Photoflash  Exposures. 

Part  III  —  Film  Developing 

Development  with  Relation  to  Exposures.  Developing 
Equipment.  Developers.  High  and  Low  Energy  Devel- 
opers. Compromise  Developers.  Temperature.  Agita- 
tion. Short-Stop  and  Fixing  Bath.  Washing  and  Drying 
the  Film.  Steps  in  Developing  a  Film.  Reticulation. 
Newton  Rings.  Storage.  Film  Cleaner.  Reducing  and 
Intensifying  Leica  Negatives. 

CHAPTER  5,    Making  of  Enlarged  Negatives: 

Three  Methods     __133 

by  John  N.  Harman,  Jr. 

CHAPTER  6.    Your  Own  Leica  Darkroom 137 

by  Willard  D.  Morgan 

The  Darkroomette.  A  Model  Darkroom.  Bathtub  Finish- 
ers. Stocking  the  Laboratory.  A  Two  Room  Laboratory. 

CHAPTER  7.    Enlarging  and  Contact  Printing 145 

by  Willard  D.  Morgan 

Selecting  the  Equipment.  Valoy  Enlarger.  Focomat 
Enlarger.  Accessories.  Making  the  Actual  Enlargements. 
Estimating  Print  Density.  Printing  Control  During 
Enlarging.  Photoflood  Bulbs.  Contact  Printing. 

CHAPTER  8.    Enlarging  Papers  and  Printing  „ 163 

by  Elbert  M.  Ludlam 

Choice  of  Paper  Stocks  and  Surfaces.  Tone  Gradation. 
Fast  and  Slow  Projection  Papers.  Contact  Papers.  De- 
velopment. Exposure.  Short-Stop.  Fixing.  Hypo  Test. 
Drying.  Ferrotyping.  Toning.  Spotting.  Presentation 
of  the  Finished  Prints.  Embossing  Prints. 

CHAPTER  9.    Copying  and  Close-Up  Photography  ___ 187 

by  Willard  D.  Morgan  —  Data  Tables  by  Henry  M.  Lester 

Importance  of  Small  Object  Photography.  Accessories. 
Sliding  Focusing  Copy  Attachment.  The  Extension  Tubes. 
The  135mm  Lens  Mount.  Data  Tables  for  Extension  Tubes 
Used  Directly  on  the  Leica.  Tables  for  Extension  Tubes 
and  Formulas.  Avoiding  Vibration  During  Copying.  Criti- 
cal Focusing  with  30x  Magnifying  Glass.  Focusing  by 
Measurement.  Fixed  Focusing.  Illumination.  Exposure 

Time.  Films  Used.  Developing.  Filters.  Auxiliary 
Reproduction  Devices.  250  Exposure  Leica. 

CHAPTER  10.    Making  Leica  Positives  for  Projection 221 

by  Willard  D.  Morgan 

What  Makes  Good  Positives.  The  Two  Positive  Printing 
Processes.  Contact  Printers.  Eldia  Printer  Directions. 
Making  the  Leica  Glass  Positive.  Projection  Paper  for 
Testing.  Mounting  the  Finished  Glass  Slide.  Film  and 
Glass  Slides  by  Projection.  Combination  Printer  Direc- 
tions. Belun  1:1  Copy  Attachment. 

CHAPTER  11.    Projecting  Leica  Pictures 237 

by  Willard  D.  Morgan 

Equipment  Available  for  Projection.  Table  of  Screen 
Distances  and  Areas.  Titles  for  Films.  Storage. 

CHAPTER  12.     Stereoscopic  Photography 249 

by  Henry  M.  Lester 

The  Stereo  Equipment.  Filters.  Sunshades  and  Film. 
Stereo  Color  Pictures.  Protecting  the  Stereos.  Using 
Two  Cameras.  Making  of  Stereo  Paper  Prints. 

CHAPTER  13.    Panorama  Photography 1 257 

by  A.  L.  Lugn,  Ph.D. 

Equipment.  Composing  the  Panorama.  Panorama  Tricks. 
Making  the  Pictures.  Printing.  Assembling  and  Mount- 
ing the  Finished  Panorama. 

CHAPTER  14.    Natural  Color  Photography 265 

by  Henry  M.  Lester  and  Rowland  S.  Potter 

Kodachrome.  Speed  and  Exposure.  Daylight  and  Arti- 
ficial Light  Filters.  Viewing  and  Projection.  Stereo- 
scopic Photography  in  Color.  Making  of  Paper  Prints. 
Three  Color  Separation  Negatives.  Chromatone  Process. 
Wash-off-Eelief  Process. 


CHAPTER  15.    The  Leica  in  Visual  Education 275 

by  Ellsworth  C.  Dent 

Educational  Use  of  Pictures.  The  Leica  Camera.  Spe- 
cial Subjects . . .  Agriculture . . .  Biological  Sciences . . .  Lan- 
guages. . . Geography. .  .History  . .  .Industrial  Arts  . .  .Ar- 
chitecture. .  .Physical  Training. .  .Physical  Sciences. 

CHAPTER  16.    The  Leica  in  Historical  Research 295 

by  James  A.  Barnes*  Ph.D. 

Obtaining  Complete  Historical  Record  Pictures.  The 
Research  Equipment.  Economical  and  Time  Saving. 

CHAPTER  17.   Copying  Books  and  Manuscripts 301 

by  Frances  W.  BinJcley 

Actual  Working  Methods.  Illumination.  Films.  Making 
and  Using  Film  Copies... The  Clerical  Side.  Copying 
Mistakes  and  Their  Remedy. 

CHAPTER  18.     The  Miniature  Camera  for  Miniature  Monsters_™._309 
by  J.  M.  Leonard 

Catching  the  Insects.  Equipment.  Photographing  in  the 
Field.  Selecting  the  Correct  Photographing  Angle.  Bring- 
ing Home  the  Catch.  Mounting  the  Insects.  Lighting. 
Ultraviolet  Light.  Equipment  for  Indoor  Work.  Photo- 
graphing at  Home.  Exposure  and  Development. 

CHAPTER  19.     Photomicrography  with  the  Leica  Camera  _____ 331 
by  H.  W.  Zieler 

When  to  Use  the  Leica  for  Photomicrography.  How  to 
Adapt  the  Leica  to  the  Microscope.  Photomicrography  of 
Living  Matter  with  the  Micro  Ibso  Attachment.  Gen- 
eral Photomicrography  with  the  Sliding  Focusing  At- 
tachment. Obtaining  Critical  Focus.  Amateur  Photo- 
micrography. Selecting  the  Microscope.  Illumination 
Apparatus.  Magnification  and  Resolving  Power.  Light 
Sources.  Filters  and  Films.  Exposure. 

CHAPTER  20.    Dental  Photography  and  Photography  of 

Small  Objects  ^357 

by  A.  Laurence  Dunn,  D.D.S. 

Equipment  Required.  Making  the  Photographs.  Focus- 
ing. Transillumination  of  Teeth.  Photographing  Re- 
flected Images.  Determining  Exposures.  Importance  of 
Keeping  Accurate  Records. 

CHAPTER  21.     The  Leica  as  an  Ophthalmic  Camera 371 

by  Henry  M.  Lester 

Equipment.  Importance  of  Focusing.  Illuminating  the 
Eye.  Flashlight  Eye  Exposures.  Leica  for  Clinical  Pho- 
tography. Use  of  the  Placido  Disc.  Portraits  of  Patients. 
Smoke  Box  Photography. 

CHAPTER  22.     Infra-Red  Photography _™_....387 

by  John  P.  Gaty 

Infra-Red  Films.  Differences  in  Infra-Red  Values.  Infra- 
Red  Photography  in  the  Field  of  Medical  Research... 
Criminology.  ..Photomicrography.  Exposure  and  Filters. 
Hypersensitizing  the  Film. 

CHAPTER  23.     Astronomical  Photography  with  the  Leica ..397 

by  Lincoln  K.  Davis 

Equipment.     Photographing  Through  a  TelescoDe. 

Ill  —  THE  IN 

CHAPTEB  24.    Candid  Photography  with  a  Leica 405 

by  Rudolf  H.  Hoffmann 

The  Scope  of  Candid  Photography.  Selfconsciousness. 
Candid  Photographs  in  Industry.  Candid  Photography  Not 
Limited  to  Any  One  Particular  Field.  Equipment. 

CHAPTER  25.   Stage  Photography 421 

by  Glenn  H.  Picket! 

Lenses  for  Theatre  Photography.  Film  and  Hypersensi- 
tizing.  Picture  Positions  in  the  Theatre.  Judging  Ex- 
posures. Slow  Exposures.  Developing  the  Negative. 
Human  Interest  Photos. 

CHAPTER  26.     The  Leica  in  the  Hollywood  Studios 431 

by  Gilbert  Morgan 

Location  Scouting.  Technical  Reference  Photos.  Make- 
Up  and  Candid  Photos. 

CHAPTER  27.    Aerial  Photography 439 

by  John  P.  Gaty 

Aerial  Compared  to  Ground  Photography.  Leica  as  a 
Profitable  Aerial  Camera.  Starting  Your  Own  Aerial 
Photo  Business.  Controlling  Perspective  by  Lens  Selec- 
tion. Making  the  Preliminary  Ground  Survey.  Filters  for 
Different  Visibilities.  Exposure.  Infra-Bed  Photography. 
Films.  Preventing  Vibration  During  Exposure.  Photo- 
graphing From  Transport  Air  Liners.  Your  Personal 
Airplane.  Aerial  Photos  at  Low  Altitudes.  Equipment. 

CHAPTER  28.     Leica  Photography  in  the  Tropics 463 

by  John  W.  Vandercook 

Equipment.  A  Dehydrating  Method.  Developing  the  Film. 

CHAPTER  29.     Photomurals  with  the  Leica 469 

by  John  T.  Moss,  Jr. 

Relation  of  Photomurals  to  the  Architecture.  Physical 
Limitations  of  Size.  Subject  Matter.  Composing  the 
Photomural.  Grain  and  Viewing  Distance.  Technical 
Photomural  Procedure. 

INDEX 482 



The  world  is  large  and  filled  with  many  things.  It  is  difficult 
to  get  acquainted  with  so  much.  Existence  seems  to  be  crowded. 
It  is  hard  to  feel  at  home  in  a  place  so  full — so  crowded  with  joys 
and  sorrows,  dreams  and  hopes,  as  well  as  the  multitude  of  objects 
that  pour  like  an  avalanche  into  our  lives.  The  products  of  the  ma- 
chine age  alone  form  a  Niagara  that  seems  overpowering.  There  is 
little  time  for  leisure,  and  work  seems  the  currency  of  our  present- 
day  life.  But  in  spite  of  all  this,  nature  continues  to  grow  and  unfold 
its  loveliness. 

Beauty  is  fearless  and  stands  proudly  beside  the  blast  furnace  or 
the  dynamo.  These  monsters  do  not  disturb  her.  She  holds  mys- 
teries greater  than  anything  done  by  the  work  of  man.  She  was 
here  long  before  the  machine  intruded  upon  our  world,  and  she  will 
remain  long  after  the  last  cogwheel  stops  its  grinding  whirl.  Thes<3 
two  powerful  forces  stand  side  by  side.  Man  must  bow  in  reverence 
before  it  all.  It  is  wonderful  to  be  able  to  see  and  know  a  few  things 
that  are  around  us.  And  it  is  not  possible  to  know  more  than  a  very 

This  idea  has  often  impressed  me.  It  is  a  little  thing,  but  it  is 
something  I  would  like  to  record.  I  would  like  to  show  my  friend  a 
symbol  of  these  two  forces  that  exist  side  by  side  in  the  crowded 
world  we  live  in.  Somewhere  I  will  find  a  little  white  flower  growing 
beside  a  black  factory  chimney.  It  will  be  worth  recording  and 
I  will  touch  a  button  and  the  hard  cold  and  uncanny  eye  of  the 
modern 'camera  will  embrace  the  idea.  I  will  take  home  a  record  of 
what  -has  been  in  my  mind.  I  will  want  to  show  it  to  my  friend  so 
that  he  can  see  at  a  glance  what  I  am  thinking  about. 

I  am  thinking  about  the  whole  big  world  and  our  little  lives. 
About  great  dynamos  whose  force  man  can  control  and  a  little  white 
flower,  growing  beside  them,  which  soon  must  wither  and  die,  a 
force  that  man  is  unable  to  control  I  am  thinking  of  animals  and 
vegetables  and  minerals  and  how  all  things  fall  into  these  three 
kingdoms  to  form  the  face  of  society.  And  I  am  thinking  that  all 
these  things  exist  only  as  a  kind  of  reflection  .  .  .  and  we  see 
them  only  as  something  that  is  projected  on  the  mirror  of  the  mind. 
This  mirror  is  a  very  mysterious  and  a  very  important  thing.  It 
controls  imagination  and  it  has  in  it  something  that  enriches  our 
lives. . 

My  friend  sends  me  a  snapshot  of  a  white  horse  frisking  across 
a  field  against  a  dark  stormy  sky.  Before  he  pressed  the  button 
he  used  the  mirror  of  his  mind.  It  is  a  fine  picture  indeed,  and  I 
compare  it  with  the  old  dray  horse  that  I  once  photographed  in  the 
streets  of  New  York.  My  picture  shows  a  poor  beast — heavy,  worn, 
sleepy  but  very  patient  and  most  reliable.  The  pictures  are  different. 
But  then  our  pictures  are  always  different.  Our  minds  are  different, 
our  eyes  are  different;  our  lives,  experiences,  and  emotions  have  all 
been  so  very  different.  And  even  if  we  both  photographed  the  same 
flowers  or  the  same  machine,  our  photographs  would  be  quite  different. 

Both  my  friend  and  I  know  something  about  the  technical  side 
of  photography.  We  both  understand  that  the  machine  we  are  using 
is  very  flexible  and  most  adaptable.  We  know  a  few  of  its  limita- 
tions and  some  of  its  possibilities.  We  have  chosen  this  very  special 
type  of  machine  that  we  use  because  of  its  extreme  flexibility  and 
because  we  believe  that  a  machine  can  become  an  instrument  of 
expression.  A  fair  amount  of  knowledge  and  a  sympathetic  feel  ins 
can  convert  a  mechanism  into  an  instrument  for  expression.  An 
artist  would  use  a  brush,  but  here  we  have  chosen  a  machine  to 
express  something  that  is  reflected  on  the  mirror  of  our  mind. 

I  am  anxious  to  show  you  some  of  these  reflections,  to  show  you 
what  T  see  in  an  animal,  in  a  plant,  or  in  a  metal  structure.  I  realize 
the  power  of  visual  perception,  and  I  know  that  I  can  tell  you  a  good 
deal  with  a  small  photograph,  for  I  do  not  trust  words  too  much. 
And  I  am  also  anxious  to  see  what  you  have  to  show  me.  I  am  eager 
to  learn  about  the  world  that  you  live  in  and  compare  it  with  the 
world  that  1  know.  They  are  the  same,  and  yet  they  are  strangely 


A  friend  has  just  sent  me  a  little  picture  that  he  has  snapped 
of  a  murderer  in  Eussia  being  led  to  prison.  He  is  an  ugly  fellow, 
and  brutality  is  written  over  his  face.  There  is  something  creepy 
and  loathsome  about  him.  But  he  is  not  unlike  a  murderer  in  Aus- 
tralia, or  France,  or  America.  I  see  now  by  that  little  picture  what 
a  slight  difference  there  is  between  them.  And  another  friend  has 
just  sent  me  a  photograph  of  lotus  flowers  floating  in  a  garden  pool 
in  China.  It  is  indeed  very  beautiful.  But  some  of  our  own  flowers 
are  also  beautiful.  They  also  sprout  and  unfold,  and  in  time  they 
wither  and  die. 

How  alike  things  are  in  different  parts  of  a  large  world.  Brutal- 
ity and  ugliness  exist  in  all  places.  And  beauty  is  there  also.  But  still 
there  seems  a  little  difference,  and  it  is  this  difference  which  is  quite 
fascinating.  A  Russian  murderer  and  a  murderer  from  Texas  are 
both  vile  creatures,  and  we  look  at  their  pictures  side  by  side  and  we 
compare  the  likes  and  the  dislikes.  And  some  of  the  flowers  that 
grow  in  China  are  very  different  from  our  own,  and  we  want  to  see 
more  and  more.  There  is  interest  in  ugliness  and  there  is  pleasure 
in  what  is  beautiful.  So  full  is  the  world.  And  many  things  are 
so  alike  and  yet  so  different. 

Water  Lily 

Yasuo  Kuniyoshi 

The  modern  lens  in  the  hands  of  a  sympathetic  and  under- 
standing person  is  an  all-seeing  eye  whose  glance  pierces  deeply  into 
surprising  recesses  of  nature.  It  traps  a  wealth  of  detail  and  lays 
bare  great  wonders.  It  often  reveals  things  that  the  eye  cannot  see. 
An  athlete  jumps  over  a  bar,  we  press  a  button,  and  in  an  instant 
that  cold  matter-of-fact  crystal  eye  has  caught  him  in  mid-air.  We 
are  surprised.  A  horse  runs  at  a  gallop,  and  his  four  legs  seem  very 
strange  indeed.  The  eye  has  failed  to  see  it,  but  the  camera  has 
caught  something  that  must  have  been  there. 

And  here  we  find  some  oil  on  the  surface  of  water,  and  it  catches 
a  glisten  of  light.  What  a  beautiful  design  it  makes!  The  human 
eye  can  hardly  take  it  in  for  it  is  moving  rapidly,  and  what  exists 
at  one  moment  is  lost  the  next.  But  we  have  captured  it  in  a  flash, 
and  we  have  brought  the  record  home  to  study.  The  water  has  now 
emptied  far  into  the  sea,  and  the  oil  on  the  surface  is  also  long  gone, 
but  we  hold  a  fairly  good  account  of  something  that  was  once  quite 
beautiful,  and  we  study  it  and  stop  to  admire  it. 

The  world  passes  before  us  in  this  strange  one-way  street  called 
time.  The  traffic  is  in  one  direction,  from  the  present  to  something 
that  very  soon  becomes  the  past.  It  cannot  be  reversed.  The  hands 
cannot  turn  backward.  And  the  things  that  we  see  now  we  will 
never  see  again.  We  are  quite  willing  to  allow  the  disagreeable  to 
pass  and  hope  these  moments  may  never  return.  But  many  things 
are  not  disagreeable,  and  we  would  be  glad  to  have  a  record  of  their 
passing  reflection. 

And  so,  with  the  aid  of  that  hard  crystal  eye,  we  trap  a  few 
sensations  that  we  know  will  never  occur  again.  We  snatch  away  a 
picture  of  a  fleeting  image,  an  idea,  a  pattern  that  surely  will  never 
be  repeated,  a  horse  making  a  record,  a  flower  growing  in  the  crevice 
of  a  rock,  strangers  walking  in  the  street,  friends  laughing  with  us, 
scenes  far  away,  and  little  incidents  close  to  our  hearts.  All  these 
and  many  more. 

But  why  should  we  want  to  hold  a  reminder  of  something  that 
no  longer  exists  ?  The  universe  is  indeed  a  large  place  and  very  full, 
and  man  is  a  very  small  creature.  And  the  little  pictures  that  he 
bothers  with  seem  so  trivial.  But  man  is  a  lonely  creature.  He  lives 
a  life  tormented  by  contradictions.  He  fears  what  he  does  not  know, 
and  he  feels  at  home  with  the  things  that  he  knows  and  understands. 
His  experiences  are  made  up  of  little  moments  out  of  the  past,  and 


Queen  Mary 

Elmar  35mm  lens,  f  :6.3,  1/40,   G  filter,  Du  Pont  Superior  film. 

Eudolf  Hoffmann 


these  little  moments,  recorded  on  the  mirror  of  his  mind,  have  widened 
his  perception  of  life.  And  so  he  is  at  peace  when  he  looks  back 
over  the  pages  that  he  has  recorded  from  his  own  existence. 

Sometimes  these  pages  are  only  vaguely  in  his  mind,  and  some- 
times they  are  pasted  into  an  album.  And  that  is  why,  no  doubt, 
my  friend  smiles  when  he  shows  me  his  little  book  of  snapshots  of 
that  never-to-be-forgotten  camping  trip  he  once  made.  What  miser- 
able snapshots  they  are;  what  wretched  photography!  He  has  since 
Improved.  But  he  smiles  as  we  turn  the  pages  because  they  bring 
back  something  that  is  very  pleasant.  They  bring  back  something 
that  he  knows  and  understands.  And  he  smiles  because  he  feels  at 
home  with  these  memories,  and  his  troubled  spirit  seems  at  peace. 
There  is  no  better  reason  why  the  following  pages  of  this  handbook 
should  be  read  very  carefully! 

But  before  we  press  the  button  we  might  remember  that  the 
two  characteristic  inventions  of  our  age  have  been  telegraphy  and 
photography.  From  the  telegraph  grew  the  telephone,  wireless,  and 
radio.  From  photography  grew  an  age  of  bad  portraiture,  silly  snap- 
shots, and  vulgar  movies.  Eealism,  that  stark  naked  child  of  our 
century,  fared  much  better  with  the  electrical  inventions.  The  optical 
inventions  retained  a  hang-over  from  our  dreamy  romantic  age. 
Photographs  were  made  soft  and  sweet.  A  bad  school  of  fuzzy  photo- 
graphy held  the  stage  for  several  generations.  Perhaps  the  reason 
for  this  is  the  fact  that  art  is  much  more  conservative  than  science. 
A  false  notion  in  the  mind  of  man  can  often  be  altered  by  a  single 
experiment,  but  his  aesthetic  sense,  controlled  mainly  by  his  emotions, 
is  slow  and  difficult  to  change.  Photography,  although  most  startling 
at  first,  was  very  slow  to  take  its  place  in  our  realistic  age. 

In  painting,  the  revolt  against  sentiment  and  tradition  occurred 
many  years  ago.  Impressionism  came  like  a  blast  and  recorded  a 
new  emotional  sense;  one  which  was  more  harmonious  with  our  age. 
And  long  before  impressionism  and  our  present-day  school  of  candid- 
camera  photography,  distinguished  artists  used  the  hard  facts  of 
realty  "as  a  subject  for  their  art.  Daumier,  Goya,  Gavarni,  and  Dela- 
croix were  only  a  few  of  the  distinguished  names. 

Somehow  or  other  it  took  many  years  for  photography  to  see  the 
world  in  the  light  of  these  artists.  It  was  stupidly  slow.  And  yet  it 
held  great  advantages.  These  advantages  are  twofold:  mechanical, 
and  psychological.  Mechanically  a  photogra^  can  be  rapidly  mul- 
tiplied and  easily  enlarged  or  reduced.  Psychologically  it  holds  a 


great  advantage  over  many  forms  of  expression,  for  a  thousand 
y/ords  in  the  ear  will  often  tell  you  less  than  a  single  glance  of  the 
eye,  and  a  photograph  speaks  in  a  language  that  needs  no  translating. 
It  is  upon  this  psychological  factor  that  a  new  form  of  newspaper, 
printed  mainly  in  pictures,  has  taken  so  great  a  hold  upon  a  vast 

About  ten  years  ago  a  definite  departure  took  place  in  the  field 
of  photography.  A  small  precision  camera  made  its  appearance. 
At  first  glance,  it  resembled  a  toy,  but  on  close  inspection  it  was 
found  to  have  those  requirements  necessary  to  become  an  instrument 
of  expression.  It  was  flexible  and  could  be  brought  into  action 
quickly.  It  had  a  very  sharp  lens,  a  good  depth  of  focus,  a  rapid 
shutter,  and  seemed  quite  complete.  It  also  had  several  disfhret 
advantages  such  as  a  crystal  focusing  device  adapted  from  the  range 
finder  used  on  guns — the  only  good  I  know  the  War  to  have  ac- 
complished— and  it  used  a  strip  of  regular  motion-picture  film.  As 
this  film  is  procurable  in  all  civilized  parts  of  the  world,  and  is  made 
with  various  fine  emulsions,  it  seemed  most  desirable.  With  tins 
little  instrument  forty  pictures  could  be  taken  upon  a  single  strip 
of  negative  in  rapid  succession.  This  was  a  great  advantage.  All 
in  all,  here  was  the  instrument  many  had  been  waiting  for.  This  was 
the  machine  that  could  record  something  that  came  to  the  mirror  of 
[•he  mind.  For  many  it  opened  up  a  new  field  of  expression.  And 
there  were  a  great  many  in  the  world  who  found  this  a  most  natural 
ruedium  of  expression,  in  fact  the  only  medium  that  they  were  capable 
of.  Here  was  an  outlet  for  pent-up  visions.  Here  was  a  way  tc 
gay  something  eloquently  for  many  who,  up  till  now,  had  remained 

In  the  ten  years  that  followed,  this  new  field  of  photography 
has  rapidly  come  forward.  Lenses  have  been  made  more  rapid,  film 
stock  much  improved,  and  special  methods  for  developing  and  en- 
larging have  been  perfected.  With  the  aid  of  numerous  attachments 
'for  special  work,  the  little  instrument  has  extended  its  bounds,  as  the 
pages  of  this  volume  testify,  in  a  most  amazing  manner.  All  this  in 
ten  years! 

The  original  camera  designed  to  do  this  type  of  work  soon 
found  competition.  Several  are  now  on  the  market  using  motion 
picture  film  and  equipped  with  range  finders  and  rapid  lenses. 
Except  for  a  very  few  special  things,  this  handbook  applies  equally 
to  all  cameras  in  the  miniature  field. 


The  pages  of  this  volume  contain  material  and  data  taken  from 
the  actual  experiences  of  a  group  of  experts,  each  a  specialist  in 
his  field.  The  information,  data  and  formulas  are  the  very  latest 
that  have  thus  far  been  perfected.  The  methods  of  photography, 
developing,  printing  and  handling  of  camera,  equipment  and  acces- 
sories, are  also  the  result  of  very  practical  experience.  Beside  this 
are  added  some  special  chapters  on  Infra-Bed,  Photomurals,  and  other 
fields  quite  new  to  this  branch  of  photography.  All  in  all,  these  covers 
embrace  the  most  complete  knowledge  on  this  subject  that  is  possible, 
at  this  time,  to  present. 

The  editors  have  proceeded  with  a  conviction  that  the  traffic  of 
ideas  was  more  important  than  merchandise.  There  are  no  secrets 
aird  "nothing  that  they  know  is  withheld  or  covered  up  with  an  air 
of  mystery.  They  recommend  no  vast  expenditure  for  equipment  or 
special  accessories.  But  they  do  ask  you  to  pause  a  moment  before 
you  press  the  button  and  acquaint  yourself  with  the  instrument  and 
read  these  pages  so  that  you  may  know  what  is  to  be  known  in  this 
new  field  of  photography.  Knowing  is  important. 

Our  age  is  distinguished  by  knowing  about  an  infinite  multitude 
of  objects.  Our  existence  seems  crowded  with  things.  When  we 
select  a  few  of  the  things  about  us,  we  display  knowledge.  Tf  what 
we  select  is  pleasing,  then  we  have  added  an  aesthetic  sense.  And  if 
we  compose  what  we  have  selected,  then  we  extend  the  aesthetic  sense 
into  something  that  has  a  meaning  and  design.  Here  creative  pho- 
tography begins.  But  now  one  more  factor  is  required:  a  technical 
knowledge.  And  here  it  is. 


Swinging  Steel 

Peter  Stackpole 


Manuel  Komroff 



In  1925  automobiles  were  on  the  verge  of  a  metamorphosis  into 
streamlining,  the  familiar  granite  ware  of  our  kitchens  turned  into 
an  array  of  colors,  women  smoked  on  the  streets,  modern  architecture 
was  being  championed  by  Frank  Lloyd  Wright,  Le  Corbusier,  Eich- 
ard  J.  Neutra,  and  others,  a  few  startling  photographs  taken  at 
unusual  angles  appeared  in  advertisements,  the  movies  were  begin- 
ning to  talk,  Eisenstein's  Potemkin  and  other  Eussian  pictures 
startled  movie  fans,  and  the  vast  majority  of  photographers  were 
making  the  same  sweet  pictures  which  their  grandfathers  made  in 
the  horse  and  buggy  days.  Let  me  add  here  that  while  all  this  pic- 
torial photography  was  good  in  its  day  and  we  have  profited  from  the 
experiences  of  these  earlier  photographers  it  is  not  sufficient  for  us 
today.  To  continue  with  the  romantic  pictorial  conceptions  is  like 
painting  a  Eembrandt  picture  today,  or  building  a  Gothic  cathedral 
in  the  shadow  of  a  New  York  skyscraper  with  all  its  modern  steel 

Into  this  teeming  world  of  change  there  was  introduced  a  small 
insignificant  camera,  it  looked  like  a  toy,  no  photographer  gave  it 
much  of  a  second  thought,  true  it  bore  all  the  stream-lining  and 
modern  earmarks  of  the  new  age,  yet  how  could  such  a  thing  which 
used  only  motion  picture  film  be  used  for  serious  photographic 
work — it  was  called  the  Leica ! 

Here  was  a  camera  which  came  as  an  interpretation  of  the  new 
developments  of  the  day.  A  camera  which  was  destined  to  com- 
pletely change  the  photographic  conceptions  of  amateur  and  profes- 
sional photographers  alike.  With  the  Leica  it  was  possible  to  secure 
pictures  in  places  which  were  formerly  taboo  for  the  ordinary  camera. 
Now  it  is  possible  to  go  into  court  rooms,  take  actual  performance 
pictures  in  theaters,  and  photograph  the  passing  American  scene  in 
all  its  naturalness.  During  the  intervening  ten  years  from  1925  to 
1935  the  Leica  gained  thousands  of  users  in  every  country  of  the 
globe.  Today  the  Leica  is  not  only  beginning  its  second  great  decade 


but  it  is  continuing  to  create  new  photographic  uses  and  operate  in 
the  hands  of  the  beginning  photographer  as  well  as  the  professional. 
Through  the  remaining  pages  of  this  book  fundamental  information 
about  using  the  Leica  will  be  presented  and  at  the  same  time  addi- 
tional chapters  included  to  give  glimpses  into  more  specialized  fields 
where  unusual  Leica  work  is  already  being  done. 

A  New  Camera  for  New  Interpretations 

It  may  be  true  that  a  modern  camera  like  the  Leica  in  the  hands 
of  a  photographer  who  is  still  thinking  from  the  angle  of  a  5  x  7  or 
8  x  10  view  camera  will  not  produce  anything  very  different.  But 
let  us  use  our  small  camera  in  a  way  which  will  be  in  keeping  with 
its  true  functions.  The  larger  cameras  gave  us  the  heebe-jeebees 
when  we  took  a  dozen  pictures  or  more  because  the  film  costs  mounted 
so  rapidly.  While  with  the  Leica  we  are  taking  yards  of  exposures 
on  35mm  motion  picture  film  at  the  rate  of  eight  pictures  per  foot 
of  film  which  cost  a  few  pennies.  Instead  of  feeling  the  usual  photo- 
graphic cramps  our  small  camera  gives  us  freedom  of  expression,  it  is 
our  visual  note  book  of  passing  events.  A  camera  which  can  be 
carried  in  the  pocket  and  used  daily  has  become  a  necessity  like  our 
watch  or  fountain  pen.  In  this  way  the  Leica  can  actually  enter 
into  our  daily  living  and  produce  photographs  which  speak  our  own 
language  and  not  the  expressions  of  past  decades. 

Therefore  why  make  the  going  difficult  by  spending  all  our  time 
striving  to  make  salon  prints  when  the  world  is  teeming  with  photo- 
graphic subjects  which  can  be  collected  through  the  lens  of  our  Leica 
camera.  A  collection  of  Leica  pictures  revealing  the  American  scene 
may  have  more  interest  and  value  than  a  few  laboriously  made  salon 
prints.  Why  not  have  more  fun  in  making  photographs  and  keep 
the  release  button  on  your  camera  working  overtime. 

During  the  past  few  years  I  have  had  an  opportunity  to  come 
in  contact  with  thousands  of  Leica  camera  users  either  personally 
or  by  correspondence.  I  have  been  with  them  in  their  triumphs  and 
assisted  them  in  their  photographic  troubles.  World  travelers  have 
brought  me  their  pictures,  leaders  of  expeditions  have  come  for  ad- 
vice, and  the  beginning  Leica  photographer  may  ask  about  the  best 
film  or  developer  to  use.  I  have  been  in  the  operating  rooms  making 
pictures  with  doctors,  in  the  air  with  pilots  who  want  to  learn  more 
about  this  miniature  camera,  and  in  industrial  plants  showing  how 
the  Leica  can  be  used  to  secure  pictures  for  advertising  purposes  or 
for  use  in  training  salesmen. 



Elmar  50mm   lens,   f:9,    1/40,   Panatomlc  film. 

Rudolf  Hoffmann 

Out  of  such  experiences  I  have  gathered  together  the  basic  ideas 
now  being  presented  in  The  Leica  Manual.  Instead  of  writing  all 
the  chapters  myself  I  felt  that  a  book  on  this  subject  would  have 
much  more  value  if  various  individuals  who  were  doing  specialized 
Leica  work  could  present  their  own  experiences.  In  this  way  the 
present  volume  has  been  written  and  I  am  certain  that  it  represents 
something  quite  different  from  the  usual  photographic  book.  As  a 
reader  you  will  find  the  very  latest  information,  developments,  and 
technique,  covering  the  entire  field  of  Leica  photography. 

The  majority  of  us  are  interested  in  what  may  be  termed  genera* 
photography  or  the  making  of  good  pictures  which  relate  to  our  own 
lives.  To  this  group  I  can  say  that  they  need  not  be  frightened  by  the 
immensity  of  the  Leica  field  which  is  covered  in  this  book.  A  thorough 
understanding  of  the  basic  photographic  principles  is  sufficient  for  making 
all  the  pictures  you  can  ever  hope  to  print.  You  only  need  a  Leica  with 
one  of  the  50mm  lenses,  an  exposure  meter,  and  a  good  fine  grain  film 
to  start  with.  With  such  a  minimum  of  equipment  you  can  easily  make 
all  the  pictures  which  may  be  classed  in  this  field  of  general  photography. 
At  first  you  can  have  a  reliable  finisher  do  your  developing  and  enlarg- 
ing. However,  as  your  interest  in  miniature  camera  work  develops  you 
will  find  that  the  real  pleasure  comes  when  you  do  your  own  finishing 
work.  As  you  expand  your  interests  the  more  specialized  chapters  in  this 
book  will  give  you  valuable  information  which  comes  from  the  experiences 
of  other  actual  Leica  users. 

It  should  be  noted  that  whenever  possible  the  Leica  accessories  are 
included  in  the  chapters  which  relate  directly  to  the  use  of  these  attach- 
ments. For  example,  all  the  Leica  lenses  are  thoroughly  described  in  the 
lens  chapter,  the  various  copying  attachments  will  be  found  in  the  chap- 
ter on  copying,  while  the  panorama  equipment  is  in  a  special  chapter 
covering  this  subject.  In  this  way  the  Leica  Manual  becomes  a  prac- 
tical handbook  for  the  Leica  users  who  are  interested  only  in  general 
photography  as  well  as  for  those  who  are  adapting  their  cameras  for 
more  specialized  work.  Today  you  may  be  interested  in  photographing 
only  general  scenes,  while  next  month  or  next  year  you  will  become  fas- 
cinated with  the  possibilities  in  aerial  photography  or  in  adapting  the 
Leica  to  your  special  hobby  or  profession.  The  wealth  of  information  in 
this  book  makes  it  possible  to  adapt  the  Leica  for  use  in  practically  any 
photographic  field. 

Why  Specialized  Chapters  Were  Included 

In  addition  to  the  more  or  less  standard  chapters  covering  the  use 
of  the  Leica  a  few  chapters  have  been  included  covering  more  specialized 
fields  .such  as  Eye  Photography,  Dental,  Photomurals,  and  Photomicrog- 
raphy. Rather  than  devote  many  pages  to  repetition  and  a  resume  of  the 
camera  accessories  readers  of  this  Manual  will  undoubtedly  appreciate  the 
efforts  of  the  editors  to  present  new  and  fresh  information  covering  the 
fascinating  field  of  Leica  photography.  A  careful  reading  of  these  spe- 
cialized chapters  will  reveal  information  which  can  be  applied  to  general 
photography  as  well  as  to  the  more  specialized  fields.  In  addition  to 
being  an  authoritative  manual  on  the  subject  of  Leica  photography,  we 
want  this  book  to  serve  as  an  inspiration  to  every  reader  by  making 
him  aware  of  the  new  possibilities  in  miniature  camera  photography. 


The  chapter  on  Photomurals  covers  a  subject  which  is  entirely  new 
I'n  the  miniature  camera  world.  Thus  a  careful  study  of  this  chapter 
will  reveal  that  photography  may  express  itself  in  new  forms  with  new 
ideas  in  keeping  with  our  more  or  less  complex  civilization.  Why  shouldn't 
our  photographic  work  interpret  our  own 'times  instead  of  slavishly  imi- 
tating the  work  of  past  masters  of  the  camera?  The  pictorial  era  in 
photography  which  flourished  from  1890  to  1925  gave  us. .  .atmosphere 
...misty  landscapes. .  .labored  compositions. .  .imitations  of  the  graphic 
arts  and  oil  paintings ...  sentimental  nudes  reclining  on  rocks  in  lonesome 
forests,  and  prints  which  had  been  worked  on  until  they  could  not  be 
recognized  as  coming  from  their  own  original  negatives. 

Thus  photography  became  muscle  bound  with  the  lavish  rules 
which  had  to  be  observed  before  the  photographer  hoped  to  have  his 
picture  accepted  in  the  exhibitions.  Even  to  this  day  we  find  judges 
of  salons  who  still  cling  to  the  romantic  days  of  photography  and 
discourage  the  new  expressions  which  are  rapidly  developing  because 
such  pioneers  as  Alfred  Stieglitz,  Edward  Steichen,  Eugene  Atget, 
Edward  Weston,  Maholy-Nagy,  Man  Ray,  and  others  felt  that  pho- 
tography is  an  art  in  itself. 

The  Editors  wish  to  note  in  offering  this  second,  revised  edition 
of  the  LEICA  MANUAL  that  due  consideration  has  been  given  to  the 
significant  advances  which  have  been  made  in  the  miniature  camera 
field.  New  natural  color  processes,  new  filters  and  newly  compiled 
authoritative  data  on  filter  factors,  a  new  direct  positive  enlarging 
medium,  new  accessories  and  lenses,  revised  and  corrected  formulas, 
new  information  on  enlarging  papers — were  incorporated  into  this 
volume.  In  addition  to  numerous  small  revisions  and  corrections 
made  throughout  the  book  it  has  been  interspersed  profusely  with 
new,  fresh,  and  exciting  photographs.  Having  sold  over  17,000 
copies  of  the  LEICA  MANUAL  in  fifteen  months— the  Editors  are 
bringing  it  up  to  date  as  the  standard  reference  for  all  miniature 
camera  photographers.  Copies  of  the  LEICA  MANUAL  have  found 
their  way  into  practically  every  corner  of  the  globe,  no  matter  how 
remote  or  isolated. 




Steel  and  Concrete 

Willard  D.  Morgan 



When  we  first  look  at  the  Leica  camera  many  questions  naturally 
arise  regarding  its  construction,  operation,  and  results  which  may 
be  expected  from  its  use.  Such  a  small  camera  as  the  Leica  requires 
a  special  technique  which  is  different  from  other  cameras.  After 
all,  any  camera  consists  of  a  lens  and  a  light-tight  box  containing 
the  film.  From  this  basic  principle  many  cameras  have  been  devel- 
oped, incorporating  hundreds  of  different  special  features  which 
tend  to  make  the  operation  of  the  camera  more  easily  adapted  to 
special  uses. 

In  the  case  of  the  Leiea,  an  'entirely  new  photographic  field  was 
entered  with  such  a  radical  change  in  camera  design  that  immediately 
many  old  habits  had  to  be  revised  in  order  to  understand  the  possi- 
bilities of  miniature  camera  work.  The  Leica  camera  required  the 
use  of  35mm  motion  picture  film,  the  use  of  fine  grain  developers, 
an  appreciation  of  the  value  of  short  focal  length  lenses  and  their 
possibilities  in  securing  photographs  which  were  radically  different. 

As  the  Leica  camera  was  developed  through  the  various  succes- 
sive stages  from  the  early  Model  A  to  the  Models  B,  C,  D,  E,  F  and 
the  present  Model  G-  with  shutter  speeds  from  1  to  1/1000  second  there 
naturally  developed  a  tremendous  interest  and  demand  for  informa- 
tion bearing  on  miniature  camera  work.  Such  information  assisted  in 
helping  all  miniature  camera  users  to  band  together  and  work  in  this 
new  photographic  field.  In  fact,  many  people  using  the  Leica  camera 
actually  belong  to  a  fraternity  "by--  themselves.  Evidence  of  this  fact 
is  to  be  seen  in  the  numerous  miniature  camera  clubs  which  have 
recently  been  formed  as  well  as  the  personal  interest  among  small 
camera  users,  and  the  large  amount  of  space  given  to  miniature 
cameras  in  the  photographic  magazines. 

In  developing  the  technique  of  miniature  photography,  it  has 
been  necessary  to  do  considerable  experimental  work  and  also  pro- 
duce many  written  articles  covering  the  important  phases  of  this 
type  of  photography  which  requires  a  technique  unfamiliar  to  the 


average  person  occasionally  using  a  box  camera.  Naturally,  the 
users  of  other  than  miniature  cameras  may  'be  confused  upon  their 
first  introduction  to  the  possibilities  of  miniature  camera  photog- 
raphy. They  will  hear  discussions  about  this  and  that  highly  cor- 
rected lens,  resolving  power,  circle  of  confusion,  depth  of  focus, 
various  different  orthochromatie  and  panchromatic  films  with  their 
advantages  and  demerits.  The  religion  of  fine  grain  will  be  ever 

Although  the  people  who  are  actually  using  the  miniature  camera 
are  deriving  immense  pleasure  from  their  particular  work,  it  may  be 
that  the  outsider  will  look  upon  such  a  field  as  a  chaotic  world. 
Miniature  camera  users  will  talk  about  enlarging  negatives  the  size 
of  a  postage  stamp  up  to  16  x  20  inches  or  more.  While  many 
workers  in  this  field  enjoy  the  experimental  angle,  it  is  true  that  over 
90%  of  the  miniature  camera  users  are  interested  in  simply  produc- 
ing good  photographs.  Most  of  us  make  our  Leica  enlargements 
either  the  postcard  size  or  the  5x7  inch  size.  Beyond  this  size,  we 
enter  the  field  of  salon  prints  or  enlargements  which  may  be  used 
for  mounting  and  hanging  in  the  home. 

For  example,  a  Leiea  user  in  Indiana  writes  the  following  after 
talking  with  one  of  the  uninitiated  miniature  camera  users  : 

"About  90%  of  the  camera  users  of  today  are  not  interested  in 
wonders.  They  do  not  possess  the  skill  of  the  expert.  They  are 
interested  in  a  camera  that  will  perform  well  in  the  hands  of  the 
ordinary  man  in  the  street,  the  man  who  is  willing  to  pay  the  price 
of  a  good  camera  but  lacks  the  skill  of  an  expert.  Does  the  Leica 
meet  this  condition?  My  opinion  is  that  it  surely  does." 

What  to  Photograph  with  a  Leica 

Photographing  with  a  Leica  can  be  one  of  the  simplest  and  most 
effective  means  of  making  a  perfect  negative.  On  the  other  hand  a 
Leica  user  can  become  -so  involved  with  his  camera,  accessories,  and  a 
multitude  of  ideas  about  miniature  camera  photography  that  he  may 
lose  sight  of  the  original  idea  behind  the  Leica.  The  Leica  was 
produced  to  simplify  photography  and  make  the  actual  use  of  this 
camera  so  convenient  that  it  would  be  indispensable.  After  all  why 
not  use  our  Leica  camera  functionally  and  become  familiar  with  the 
many  intriguing  uses  to  which  this  camera  may  be  applied. 

Before  starting  to  take  pictures  with  our  Leica  let's  stop  a 
moment  and  become  familiar  with  the  photographic  possibilities 
open  to  the  miniature  camera  user. 


Leica  Equipment 

1.  Because  of  the  small  size  of  the  Leica  it  can  be  concealed  in  the  pocket 
and  later  used  for  making  pictures  in  practically  any  place  where  there 
is  sufficient  light  to  make  an  exposure.     You  may  catch  the  unposed 
positions  of  people  in  a  railroad  waiting  room,  or  the  information  clerk 
carefully  explaining  some  route  to  a  customer.    The  theater,  night  club, 
public  gatherings,  street  scenes,  and  everywhere  people  meet  there  will 
be  pictures  for  the  Leica  user  to  make.    Such  photographs  tell  their  own 
story,  and  show  in  a  moment  that  the  photographer  must  have  had  a 
miniature  camera  and  worked  quickly  in  order  to  make  the  exposure. 

2.  Use  the  Leica  for  making  twenty  or  thirty  successive  portraits  of  the 
same  person  and  thus  catch  a  more  complete  interpretation  of  character. 

-  These  views  will  portray  a  wide  range  of  interesting  expressions  instead 
of  the  usual  one-view  portraits  which  are  made  with  the  larger  cameras. 

3.  This  same  idea  of  making  sequence  pictures  can  be  used  for  photograph- 
ing children  who  are  forever  scampering  about.     Catch  these  colorful 
expressions  of  the  youngsters  and  arrange  the  resulting  pictures  in  an 
attractive  series  in  your  album. 

4.  When  traveling  with  the  Leica  you  will  find  that  it  is  easier  to  take 
many  more  than  the  ordinary  number  of  pictures  and  thus  give  a  more 
complete  record  of  your  trip.    With  the  cost  of  film  so  small  there  is  no 
reason  why  many  hundreds  of  interesting  pictures  cannot  be  obtained, 
even  on  a  short  trip  of  only  a  few  days. 

5.  At  the  horse  races,  athletic  events,  yacht  races,  and  other  similar  events 
the  Leica  will  fit  into  the  occasion  without  being  in  the  way  and  thus 
take  the  edge  off  an  otherwise  glorious  time. 

There  are  naturally  many  other  uses  for  the  Leica.  One  of  the  pleas- 
ures of  owning  this  camera  is  to  discover  some  of  these  uses  for  oneself 
and  thus  satisfy  one's  creative  instincts  in  producing  something  a  little 
different  from  "the  boys  with  the  big  cameras".  In  this  book  the  writers 
have  endeavored  to  present  their  photographic  methods  as  well  as  to  convey 
some  of  the  pleasures  to  those  who  are  seeking  new  discoveries  and  a  more 
complete  understanding  of  miniature  camera  photography.  To  begin  with, 
let's  start  with  the  equipment  itself. 

Know  Your  Leica 

As  the  Leica  has  been  constructed  quite  differently  from  most 
cameras  we  should  become  more  familiar  with  the  important  working 
parts.  Let's  take  a  Leica  in  our  hands  and  look  at  it  ...  wind  and 
release  the  shutter  .  .  .  set  the  speed  dial  at  various  stops  .  .  .  pull 
the  lens  'barrel  out  and  lock  it  by  a  slight  turn  to  the  right  .  .  .  turn 
the  focusing  mount  of  the  lens  and  watch  the  images  move  out  of 
focus  or  into  focus  through  the  range  finder  which  is  coupled  with 
the  lens  .  .  .  open  and  close  the  iris  diaphragm  of  the  lens  .  .  . 
study  the  depth  of  focus  scale  at  the  base  of  the  lens  mount  .  .  .  try 
the  slow  shutter  speeds  on  the  Model  F  Leica  .  .  .  move  the  counting 
dial  to  zero  after  winding  the  shutter  .  .  .  move  the  small  lever 
between  the  winding  knob  and  the  time  setting  dial  to  E  or  reverse 
.  .  .  pull  up  and  turn  the  rewind  knob,  then  push  it  back  into  posi- 
tion and  change  the  lever  back  to  A  or  advance  .  .  .  adjust  the  com- 


pensating  eyepiece  of  the  range  finder  for  distances  under  15  feet 
.  .  open  the  baseplate  .  .  .  remove  the  take  up  spool  and  film 
magazine  .  .  .  try  loading  and  unloading  several  times  before  replac- 
ing the  baseplate  .  .  .then  go  back  to  winding  and  clicking  the 
shutter,  and  at  the  same  time  focus  on  actual  objects  and  imagine 
that  you  are  making  actual  pictures. 

All  this  may  at  first  seem  complicated  but  once  you  have  gone 
through  this  routine  the  actual  operation  of  the  Leica  will  seem 
extremely  simple.  You  will  become  familiar  with  a  new  type  of 
camera  which  has  been  built  to  eliminate  the  usual  amateur  photo- 
graphic troubles,  such  as  double  exposures,  out  of  focus  pictures, 
under-exposures  because  of  slow  lenses  or  failure  to  stop  rapid  motion 
because  of  slow  shutter  speeds. 

To  make  Leica  pictures  it  is  not  necessary  to  own  the  very 
latest  model  camera  with  all  the  interchangeable  lenses,  filters,  cases, 
and  a  hundred  other  accessories  which  could  be  used.  No,  all  this 
equipment  is  for  those  who  can  afford  it  and  also  for  use  when  they 
have  advanced  to  the  point  where  more  specialized  photography  is 
required  with  the  Leica. 

Fig.  7    Leica  Model  F  or  G  Equipped  with  50mm  f  :2  Summar  lens.   Model 
G  Available  in  Chrome  Finish  Only 

Your  Beginning  Leica  Equipment 

All  you  need  as  a  beginning  Leiea  user  is:  a  Leica  camera 
equipped  with  one  of  the  50mm  lenses,  an  exposure  meter,  and 


Leica  Equipment 

several  rolls  of  film.  With  this  outfit  you  can  take  thousands  of 
excellent  pictures  and  never  miss  the  use  of  additional  accessories. 
Many  fine  picture  are  still  being  made  with  the  early  Leica  Models 
A  and  C.  The  basic  idea  of  the  Leiea  has  never  changed  since  the 
day  it  was  first  introduced  in  1924.  Therefore  it  is  unnecessary  to 
be  disturbed  by  the  haunting  thought  that  it  takes  a  fortune  to 
operate  a  Leica.  On  the  contrary,  once  the  camera  is  purchased  the 
operation  cost  is  drastically  cut  when  compared  to  the  larger 

How  to  Make  Your  First  Leica  Picture 

"When  preparing  to  make  your  first  Leica  picture  there  are  a 
few  important  points  to  observe  as  follows : 

1.  Place  the  film  magazine  containing  the  unexposed  film  into  the 
camera  after  removing  the  base  plate  and  take  up  spool.  Figure 
8  shows  the  position  of  the  film  when  properly  loaded. 



Fig.  8     Dotted  Line  Shows  Correct  Position  of  Film  when  Loaded  in  the 
Leica  camera.    M — Take  up  Spool,  W — Film,  D — Film  Magazine 

2.  Check  to  make  certain  that  the  reversing  lever,  located  between 
the  winding  knob  and  the  speed  dial,  is  at  A  or  advance.  (This 
lever  is  moved  over  to  E  after  all  the  exposures  have  been  made 
and  the  film  is  to  be  rewound  into  the  original  magazine.) 
Turn  the  winding  knob  and  click  the  shutter  twice  in  order  to 
pass  the  film  which  was  exposed  to  the  light  while  loading.  Then 
wind  the  shutter  a  third  time  and  also  set  the  counting  dial  at 
picture  number  one  opposite  the  small  arrow.  If  preferred  the 
counting  dial  can  be  set  at  zero  after  the  second  wind  of  the 
shutter.  Then  after  the  shutter  has  been  released  the  camera  is 
ready  for  making  pictures. 

Determine  the  correct  exposure  with  the  Leicameter,  Leicascop 
or  other  reliable  meter. 

Set  the  shutter  speed  on  the  dial  by  slightly  lifting  and  turning 
to  the  proper  position  required.  Before  setting  the  shutter 
speed  turn  the  winding  knob  one  complete  turn.  In  the  case  of 




the  Model  F  Leica  the  slow  speed  dial  is  set  at  any  desired  stop 
between  1  second  and  l/20th  of  a  second  after  the  top  dial  has 
been  set  at  20-1  which  represents  l/20th  to  1  full  second  on  the 
slow  speed  dial.  When  l/20th  is  to  be  used  on  the  Model  P  set 
both  dials  at  the  figure  20. 

6.  Full  out  the  lens  barrel  and  lock  it  into  position  by  a  slight  turn 
to  the  right,  in  case  one  of  the  50mm  lenses  is  in  use. 

7.  Set  the  iris  diaphragm  to  the  proper  opening  which  has  already 
been  determined  by  using  the  exposure  meter. 

8.  Secure  exact  focus  by  looking  through  the  range  finder  eyepiece 
and  at  the  same  time  rotate  the  lens  barrel  back  and  forth  until 
the  two  images  coincide.    (The  earlier  Models  A,  C,  and  E  Leica 

Fig.  9  Rear  View  of  Range 
Finder  and  View  Finder.  Note 
Magnifying  Eyepiece  on  Range 
Finder  Adjustable  for  Sharp 
Focus  on  Near  Objects  under 
15  Feet  When  in  Upright  Posi- 

cameras  do  not  have  the  built-in  range  finder  with  automatic 
lens  coupling  as  in  the  later  models.  However  these  earlier 
models  may  be  converted  to  a  later  model,  or  a  separate  range 
finder  may  be  used  for  determining  the  distances.)  "When  only 
one  image  is  seen  through  the  range  finder  the  subject  is  in  exact 
focus.  Shift  the  eye  to  the  right  (when  holding  the  camera  hori- 
zontally) and  compose  the  picture  through  the  view  finder.  When 
you  are  ready  to  make  the  picture,  press  the  release  button 
gradually  and  thus  make  the  exposure.  You  have  now  taken 
your  first  Leica  picture ! 

9.  Keep  on  taking  pictures  until  you  have  used  up  the  entire  roll 
,  of  30  or  36  exposures.  Try  various  shutter  speeds,  outdoor  and 
indoor  views.  Place  your  Leica  in  its  case  or  in  your  pocket, 
then  see  how  fast  you  can  whip  it  into  action  and  at  the  same 
time  remember  the  points  which,  are  essential  for  making"  a 

1.  Determine  the  exposure 

2.  Pull  out  and  lock  the  lens  into  position 

3.  Set  the  lens  diaphragm  stop 

4.  Turn  the  shutter  winding  knob  one  complete  turn 

5.  Set  the  shutter  speed  dial 

6.  Look  through  range  finder  and  determine  focus 


Leica  Equipment 

7.  Shift  your  eye  to  the  view  finder  and  compose  picture 

8.  Gradually  press  the  shutter  release  button  and  make  the 

10.  Caution  .  .  .  When  pressing"  the  release  button  with  the  fore- 
finger avoid  jerking  the  camera  by  abruptly  pushing  the  release. 
Instead,  hold  the  finger  on  the  release  and  gradually  squeeze 
the  button  down,  similar  to  the  gradual  trigger  squeeze  which  is 
so  essential  to  accurate  shooting  with  a  gun.    Place  thumb  of 
right  hand  under  the  base  plate  to  counteract  the  downward 
action  of  the  forefinger.     Wherever  possible  it  is  best  to  use 
shutter  speeds  of  l/40th  or  l/60th  of  a  second  or  faster  when 
the  camera  is  held  in  the  hands,  in  order  to  avoid  any  possible 
motion  during  exposure. 

11.  When  you  reach  the  end  of  the  film  roll  the  shutter  winding 
knob  will  not  turn  .  .  .  don't  force  it  and  try  to  squeeze  another 
exposure  onto  the  film.    Instead,  just  move  the  reversing  lever 
to  R  and  rewind  all  the  film  back  into  the  film  chamber.     The 
base  of  the  release  button  will  turn  during  this  procedure  and 
will  stop  the  moment  the  film  pulls  away  from  the  take  up 
spool  in  the  camera.    The  film  magazine  may  be  removed  from 
the   camera   after  the  winding  has  been   completed   and  the 
reversing  lever  moved  back  to  A  or  advance. 

12.  Each  time  the  shutter  winding  knob  is  turned,  when  there  is 
film  in  the  camera,  the  rewinding  knob  turns  in  a  reverse  direc- 
tion (counterclockwise),  thus  indicating  that  the  film  is  properly 
passing  to  the  next  exposure. 

Loading  the  Leica  Film  Magazine 

The  standard  Leica  Film  Magazine,  sometimes  referred  to  as 
model  B,  has  been  constructed  to  hold  about  5%  feet  of  35mm  cine 
film  which  is  sufficient  to  make  up  to  36  double  frame  exposures,  24 
by  36mm  in  size.  This  cylindrical  magazine  contains  three  parts : 
the  outer  shell  B1,  the  inner  shell  B2,  and  the  center  spool  B3.  The 
guide  groove  on  the  inner  shell  and  the  pin  inside  the  outer  shell 
opposite  the  safety  spring,  assist  in  opening  and  closing  the  film 

To  assemble  the  magazine  first  insert  the  daylight  film  spool 
into  the  inner  shell  with  the  tip  of  the  film  in  the  opening  of  the 
spool  chamber.  It  is  a  good  plan  to  bend  back  the  tip  end  of  the 
film  in  order  to  make  it  easier  to  pull  the  film  out  of  the  magazine, 
and  also  to  prevent  the  film  from  drawing  back  into  the  magazine 
before  loading  into  the  camera.  Next,  introduce  the  inner  shell  with 


spool  into  the  outer  shell  with  both  rectangular  openings  together 
and  open.  When  the  inner  shell  comes  to  a  stop  turn  it  to  the  left 
or  anti-clockwise  until  the  safety  spring  clicks  into  the  locked  posi- 
tion. Before  the  chamber  is  closed  pull  the  film  out  several  inches. 
The  film  magazine  can  only  be  opened  after  the  safety  spring  has 
been  slightly  lifted  and  the  inner  shell  turned  to  the  left  or  clock- 
wise. The  inner  shell  is  then  withdrawn  and  the  film  removed 
either  in  the  daylight  or  in  the  darkroom,  depending  upon  the  film 
packing  used. 


Fig.  10    The  Model  B  Leica  Film 

B  =  Complete  Spool  Chamber  Model  B 

B1  =  Outer  Shell 

B2  =  Inner  Shell 

B3  =  Center  Spool 

B*  =  Spring  of  Center  Spool 

B5  =  Milled  Knob  of  Center  Spool 

B6  —  Slots  of  Spool  Chamber 

BT  =  Knob  of  Spool  Chamber 

B8  =  Safety  Spring 

The  Outside  Parts  of  the  Models  F  and  G  Leica  Cameras 

1.  Winding  knob . . ,  one  complete  turn  winds  shutter,  advances  film  to  the 
next  picture,  and  registers  one  count  on  the  dial  7  at  base  of  knob. 

2.  Shutter  release  button ...  with  protective  bushing  which   may  be  un- 
screwed and  a  Wire  Eelease  screwed  over  the  release  button. 

3.  Shutter  speed  dial. .  .for  .setting  speeds  from  l/20th  to  l/500th  of  a 
second  and  time  exposure.     Dial  10  is  used  for  setting  the  slower 
speeds  between  l/20th  and  1  second.    Winding  knob  1  must  be  wound 


Lelca  Equipment 

one  complete  turn  before  setting  speed  dial  8.  Once  this  dial  is  set  it 
need  not  be  changed  for  successive  exposures  unless  the  shutter  speed 
is  to  be  changed.  Leica  Model  G  has  an  additional  shutter  speed  of 
l/1000th  of  a  second. 

4.  Clip... for  holding  Universal  View  Finder,  Stereo  Attachment,  Level, 
Reflecting  View  Finder,  Angle  View  Finder,  and  other  attachments.    A 
small  engraved  arrow  on  one  flange  of  this  clip  indicates  the  shutter 

5.  Built-in  range  finder. .  .which  has  an  interior  mechanism  connecting 
with  the  lens  mount  for  determining  correct  distances  and  focus. 

6.  Rewinding  knob. .  .which  is  pulled  up  and  turned  to  rewind  the  exposed 
film  back  into  the  film  magazine. 

7.  Counting  dial... which  automatically  records  each  photograph  taken. 
On  this  counting  dial  there  are  two  small  lugs  used  for  turning  the  dial, 
anti-clockwise  and  against  the  direction  of  the  arrow  on  the  winding 
knob,  to  the  zero  mark. 

8.  Counting  arrow. .  .indicating  the  number  of  photographs  taken. 

9.  Reversing  Lever. .  .which  disengages  the  automatic  coupling  of  film  ad- 
vance and  shutter  mechanism  when  the  exposed  film  is  to  be  rewound 
back  into  the  film  magazine.    When  this  lever  is  set  at  R  it  operates 
somewhat  similarly  to  a  clutch  on  an  automobile  by  disconnecting  the 
camera  mechanism.    Keep  the  lever  at  A  while  making  exposures. 

10.  Slow  shutter  speed  dial... which  turns  to  change  the  shutter  speeds 
between  l/20th  and  1  full  second.  There  is  also  a  time  exposure  setting 
on  this  dial. 

1.    Winding  Knob 

2.    Shutter  Release 

3.    Shutter  Speed  Dial 
4.    Finder  Clip 

5.    Built-in  Range  Finder 

.6.    Rewinding  Kno 

Counting  Dial 

Counting  Arrow 

Fig.  11 

Reversing  Lever. 
A  =  Advancing  Film 

R  =  Reversing  Film        |  I        I          3.3.    View  Finder 

10.    Slow  Speed  Dial  |       1^    Diaphragm  Ring 

11.    Lens  Focusing  Lever 

Outside  Parts  of  the  Leica  Camera. 


11.  Lens  focusing  lever. .  .which  is  pressed,  to  release  the  lens  mount  from 
the  infinity  setting,  and  moved  back  and  forth  while  the  eye  looks 
through  the  range  finder  until  the  double  image  of  an  object  comes 
into  focus  and  only  one  image  is  to  be  seen. 

12.  Knurled  diaphragm  ring ...  with  diaphragm  markings  which  is  turned 
for  setting  the  proper  lens  opening  in  the  Summar  f  :2  lens.    The  50mm 
Elmar  and  Hektor  lenses  have  the  diaphragm  settings  on  the  front  of 
the  lens  mount. 

13.  View  Finder. .  .which  includes  the  full  area  of  the  image  registered  by 
the  50mm  lenses.  The  Universal  View  Finder  covers  the  picture  areas  of 
the  other  Leica  lenses. 

The  Interior  Mechanism  of  the  Leica 

Fig  12.  Diagramatical  view  of  the  Leica  short  base  built-in  range  finder. 
The  two  arrows  point  toward  the  object  which  will  be  in  exact  focus  when 
the  image  coming  through  the  right  hand  movable  prism  is  projected  and 
coincides  with  the  image  which  is  seen  through  the  prism  mirror  on  the 
left.  As  the  lens  turns  the  base  of  the  mount  moves  in  or  out  and  thus 
moves  the  small  lever  which  is  attached  to  the  right  hand  prism. 

Fig.  13    Back  cross-section  view  of  the  Leica  showing  focal  plane  shutter, 
film,  and  all  the  actual  working  parts  of  the  camera  in  cross-section. 


Leica  Equipment 

Fig.  14  Looking  down  on  cross-section  view  of  range  finder  and  view 
finder  housing.  Note  position  of  range  finder  prisms,  the  right  prism  is 
moved  by  the  bar  which  contacts  the  flange  of  the  rotating  lens  mount. 

Fig.  15     Top  cross  section  view  of  the  Leica  showing  position  of  the  film 
focal  plane  shutter,  lens,  and  other  working  parts. 

Daylight  Loading  and  Unloading  Film  Spools 

It  is  more  convenient  to  secure  Leica  films  already  loaded  in  film 
magazines  or  on  an  individual  film  spool  which  is  inserted  into  the  Leica 
film  magazine  when  required.  The  Agfa,  Eastman,  Gevaert,  Mimosa,  and 


Fig.  16     Showing  Method  of  Inserting  the  V2  Lock  in  the  Earlier  Leica 


Perutz  films  are  packed  in  complete  magazines  ready  for  instant  use  in  the 
Leica,  These  film  magazines  are  daylight  loading  and  unloading  and  greatly 
simplify  the  film  loading  process.  Figure  8  shows  this  type  of  film 
cartridge  in  position. 

Some  of  the  earlier  Leica  cameras  may  require  a  slight  change  as 
shown  in  figure  16  before  this  new  type  of  film  cartridge  can  be  inserted. 
The  Vi  lock  is  replaced  by  the  V2  lock  as  shown  in  the  illustration.  The 
change  over  is  done  by  removing  the  two  screws  which  hold  the  Vi  lock  in 
position,  and  then  replacing  with  the  V2  lock.  The  V2  lock  may  be  secured 
from  your  Leica  dealer. 

The  Du  Pont  Leica  films  are  spooled  with  a  black  paper  leader  which 
protects  the  film  until  it  is  loaded  into  the  metal  film  magazine  and  then 
inserted  into  the  Leica.  This  film  spool  may  also  be  unloaded  in  daylight 
after  the  film  has  been  exposed  and  rewound  back  onto  the  spool.  Com- 
plete directions  for  loading  are  packed  with  each  roll  of  Dupont  film. 

When  the  film  magazine  is  to  be  unloaded  in  the  darkroom  the  paper 
leader  on  the  Du  Pont  film  can  be  cut  off  after  loading  into  the  film 
magazine.  The  film  end  is  then  inserted  directly  into  the  take  up  spool  clip 
without  first  winding  all  the  paper  leader  on  the  spool  before  inserting  into 
the  camera. 

Occasionally  one  wishes  to  remove  the  film  roll  after  half  a  dozen  or 
more  exposures  have  been  made.  This  may  be  necessary  when  a  different 
film  is  required  or  when  some  of  the  exposed  section  of  the  film  is  to  be 
developed.  Before  rewinding  the  film,  note  the  number  of  exposures  taken. 
Then,  after  moving  the  rewind  lever  to  R,  raise  and  turn  the  rewind  knob 
until  the  film  pulls  loose. .  .then  stop  in  order  to  prevent  the  film  leader 
from  going  back  into  the  film  chamber.  Remove  the  film  magazine  with 
the  two  or  three  inches  of  the  film  leader  still  outside  of  the  magazine. 
Later  this  same  film  roll  may  be  replaced  in  the  camera,  winding  and 
clicking  the  shutter  as  many  times  as  necessary  to  move  the  exposed 
portion  of  the  film  through  the  camera.  The  lens  cap  should  naturally  be 
left  over  the  lens  during  this  process. 

Fig.  17     Method  of  Cutting  Film  for  Inserting  into  Magazine  Spool 


Leica  Equipment 

Fig.  18  Method  of  Cutting 
Film  End  Which  Projects 
from  Magazine  and  Inserts 
into  Take  Up  Spool  when 
Loading  the  Leica  camera. 

Loading  Bulk  Film 

Bulk  film  may  be  purchased  in  almost  any  length  from  15  feet  to  1000 
feet  at  prices  ranging  from  2  to  8  cents  per  foot.  As  the  Leica  will  expose 
8  pictures  per  foot  of  film  it  is  an  easy  matter  to  figure  out  the  amount  of 
bulk  film  required  after  allowing  for  the  few  frames  which  are  lost  at  the 
beginning  and  end  of  each  Leica  loading. 

When  loading  the  Leica  film  magazine  with  film  from  a  large  roll  it  is 
necessary  to  carry  out  all  operations  in  complete  darkness,  unless  the  proper 
safety  lights  are  used.  In  the  case  of  fast  panchromatic  films  complete 
darkness  is  essential.  Therefore  it  is  best  to  practice  loading  the  film 
magazine  in  daylight  with  a  short  piece  of  film  in  order  to  become  com- 
pletely familiar  with  the  operations.  You  can  even  shut  your  eyes  during 
this  practicing. 

When  cutting  film  from  the  larger  roll  care  should  be  taken  to  cor- 
rectly taper  the  end  of  the  film  which  attaches  to  the  spool  and  also  the 
leader  end  which  is  partly  cut  away  as  shown  in  the  illustrations.  A  Film 
Trimming  Guide  is  available  for  this  cutting. 

When  the  Film  Trimming  Guide  is  used  for  cutting  the  spool  end  of 
the  film,  the  guide  is  opened  and  the  film  inserted  through  the  narrow 
slot  with  the  emulsion  side  down.  Let  the  end  of  the  film  project  slightly 
beyond  the  end  of  the  guide,  close  the  trimmer  and  then  cut  the  film  as 
shown  in  the  illustration.  Always  make  certain  that  no  finger  prints  are 
left  on  the  emulsion  side  of  the  film. 

Now  place  the  other  end  of  the  five  foot  length  of  film  into  the  Trim- 
ming Guide  as  shown  in  figure  18  and  make  a  longer  cut  in  order  to  make 
it  easier  to  load  the  film  into  the  camera  later.  It  should  be  noted  that  no 
cut  is  made  through  a  perforation  on  the  film  edge.  The  Film  Trimming 
Guide  has  two  pins  which  engage  in  the  perforations  and  hold  the  film  in 
the  proper  cutting  position.  Place  the  film  into  the  guide  with  the  emulsion 
side  facing  the  two  pins.  The  film  ends  can  be  cut  with  a  scissors  without 
a  Trimming  Guide  after  a  little  practice. 


Winding  the  Film 

In  order  to  make  it  easier  to  wind  the  film  spool  with  fresh  unex- 
posed  film  a  Hand  Film"  Winder  and  also  a  stationary  Mechanical  Film 
Winder  are  available.  The  operation  of  these  winders  may  be  studied  from 
the  accompanying  illustrations.  The  Hand  Film  Winder  is  slipped  into  the 
bottom  of  the  center  spool  and  engages  the  cross-pin  for  turning. 

Fig.  19     Loading    Film    Spool    by 
Means  of  a  Mechanical  Winder. 
Also  for  use  with  Model  FF  Spools. 

Fig.  20 


Hand  Film 

The  Mechanical  Film  Winder  should  be  attached  to  a  table  or  heavy 
block  of  wood.  A  slit  core  receives  the  film  spool  ready  for  the  film  winding 
process.  After  the  film  end  has  been  fixed  to  the  center  spool,  the  film 
should  be  wound  tightly  during  the  turning  of  the  handle.  Do  not  attempt 
to  pull  the  film  and  thus  tighten  the  film  already  rolled  on  the  spool. .  .this 
will  produce  scratches. 

The  Earlier  Leica  Models 

Although  the  first  Leica  model  was  made  by  Oscar  Barnack  in  1914  it 
was  not  until  1924  that  actual  production  began  with  the  introduction  of 
the  Model  A  Leica  without  the  interchangeable  lens  feature.  This  camera 
contained  all  the  Hasic  features  which  are  to  be  found  in  the  latest  Model  F 
Leica,  with  the  exception  of  built-in  range  finder  and  slow  shutter  speeds. 
During  the  ten  years  between  1925  and  1935  new  improvements  on  the 
original  design  created  new  models:  Thus: 

1.  A  camera  with  Compur  shutter  instead  of  the  usual  focal  plane  shutter 
was  introduced  as  the  Model  B  Leica. 

2.  Interchangeable  lenses  brought  out  the  Model  C  Leica  (also  known  as 
Model  I). 

3.  A  built-in  focusing  range  finder  adapted  to  couple  to  the  various  inter- 
changeable lenses  produced  the  Model  D  Leica  (also  known  as  Model  II). 


Leica  Equipment 

Fig.  21  The  Pioneer  Leica 
Constructed  in  1914  by  Oscai 

Fig.  22    The  Model  E  Leica 
with  Fokos  Range  Finder. 

Fig.  23  Detail  of  Leica  Show- 
ing Fokos  Range  Finder  in 
Position.  Range  Finder  may 
be  Turned  When  Making  New 
Shutter  Adjustments.  . 

4.  A  horizontal  Short  Base  Range  Finder  and  the  pull-up  type  of  rewind 
knob  identify  the  Model  E  Leica  (similar  to  Model  I). 

5.  An  additional  slow  shutter  speed  mechanism,  with  speeds  down  to  1  full 
second,  was  added  to  the  Model  D  type  and  thus  created  the  Model  F 
Leica   (also  known  as  the  Model  111). 

6.  By  the  addition  of  a  1/1 000th  of  a  second  shutter  speed  the  present 
Model  G  Leica  (also  known  as  the  Model  Ilia)   was  produced. 


Note.  Outside  of  the  United  States  the  Model  C  Leica  is  known  as 
Model  I,  the  Model  D  as  Model  II,  the  Model  F  as  Model  III, 
the  Model  G  as  Model  Ilia,  and  the  Model  FF  as  the  250  Ex- 
posure Leica.  It  will  be  noted  that  the  original  Model  A  Leica 
was  simply  known  as  the  Leica  Camera  without  a  model  number. 

7.  With  the  addition  of  film  chambers  to  hold  up  to  33  feet  of  film  250 
Exposure  Model  FF  Leica  was  introduced. 

8.  Finally,   the    Single   Exposure   Leica   was    made   to   meet    special    re- 

Fig.  24    The  250  Exposure  Leica  Model  FF. 

Fig.  25    Loading  the  Leica  Model  FF.    After  Exposures  Have  Been  Made 
Film  is  not  Rewound.    Note  Special  Film  Trimming  Guide. 

This  brief  summary  of  the  various  Leica  models  will  be  of  special 
value  to  many  people  who  intend  to  "purchase !  either  new  or  used  Leica 
cameras.  The  latest  direction  book  which  is  supplied  with  every  new 


Leica  Equipment 

camera  contains  information  about  the  operation  of  the  Leica.  This  infor- 
mation can  be  applied  to  all  Leica  models.  Therefore  it  will  not  be  nee-. 
essary  to  reprint  detailed  descriptions  and  directions  on  these  cameras. 
One  of  the  remarkable  features  of  the  Leica  is  the  fact  that  it  is  possi- 
ble .to  convert  any  of  the  earlier  models  to  the  very  latest  model.  This 
fact  alone  is  really  a  tribute  to  the  inventor  who  was  able  to  design  the 
basic  features  of  the  Leica  so  perfectly. 

Leica  Accessories 

Along  with  the  development-  of  the  Leica  there  naturally  came 
the  production  of  many  accessories  which  served  to  extend  the  use 
of  the  camera  into  many  new  photographic  fields.  With  the  introduc- 
tion of  various  interchangeable  lenses  there  was  a  need  for  the  Vidom 
Universal  View  Finder.  The  various  enlargers  made  it  possible  for 
the  average  amateur  to  make  excellent  enlargements  from  Ms  Leica 
negatives.  Stereo,  copy,  micro,  panorama,  and  other  attachments 
came  in  rapid  succession  to  round  out  the  universal  use  of  this 
camera.  Most  of  these  accessories  are  carefully  described  in  the 
various  chapters  to  which  they  relate.  However  a  few  of  the  impor- 
tant accessories  not  illustrated  elsewhere  in  this  book  are  shown  in 
this  chapter. 

Vidom  Universal  View  Finder 

As  the  direct  optical  view  finder  in  the  Leica  is  only  used  for 
the  50mm  lenses  it  is  necessary  to  use  the  Vidom  Universal  View 
Finder  for  all  other  interchangeable  Leica  lenses.  This  finder  con- 
tains an  adjustable  diaphragm  which  is  easily  moved  by  turning  a 
calibrated  ring  to  include  the  field  of  view  of  any  Leica  lens.  The 
diaphragm  is  rectangular  and  the  sides  retain  the  standard  2  to  3 
proportion  of  the  Leica  negative  size  when  changed  for  any  field  of 
view.  Thus  if  the  Vidom  Finder  is  used  with  a  90mm  lens  the 
calibrated  ring  is  turned  to  the  figure  9  (opposite  the  long  line)  and 
the  adjustable  diaphragm  will  then  include  the  exact  field  of  view 
between  30  feet  and  infinity.  "When  taking  close-up  pictures  between 

Fig.  26  Vidom  Universal  View 
Finder  Used  for  Determining  Field 
of  View  of  the  Various  Leica 


to  6  feet  set  the  figure  representing  the  focal  length  of  the  lens 
opposite  the  short  line  on  the  finder.  For  distances  between  6  and  30 
feet  set  the  figure  between  the  two  index  lines. 

A  parallax  adjusting  lever  is  located  at  the  rear  base  of  the  Vidom 
Finder  with  calibrations  of  3^,  5,  7,  15  feet,  and  °°  or  infinity.  As 
the  finder  is  attached  to  the  top  of  the  Leica  and  not  directly  behind 
the  lens  this  parallax  adjusting  lever  is  used  to  make  the  proper 
inclination  of  the  finder  in  order  to  include  the  exact  field  covered 
by  the  lens.  Thus  this  finder  is  used  by  many  Leica  owners  for  taking 
close-up  photos  with  the  5Qmm  lenses.  The  direct  view  finder  already 
attached  to  the  Leica  does  not  have  this  parallax  adjusting  feature. 

The  eyepiece  of  the  Vidom  Finder  rotates  in  a  90  degree  arc  in  order  to 
keep  the  image  right  side  up  when  using  the  camera  in  the  horizontal  or 
vertical  positions.  When  using  this  finder  to  photograph  rapidly  moving 
objects  it  is  best  to  keep  both  eyes  open  in  order  to  make  it  easier  to  keep 
the  object  in  the  center  of  the  finder. 

Another  valuable  use  of  the  Universal  Finder  is  in  determining  the 
field  of  view  in  pictorial  photography  without  the  camera.  By  sighting 
through  the  finder  one  can  easily  determine  if  there  is  a  picture  worth  taking 
without  the  necessity  of  removing  the  camera  from  the  case.  Such  a  con- 
venience is  of  special  value  when  working  with  the  longer  focal  length 

Wide  Angle  View  Finder 

Although  the  Universal  View  Finder  includes  the  field  of  the  35mm 
wide  angle  lens  there  are  times  when  the  smaller  wide  angle  direct  view 
finder  is  used.  This  wide  angle  finder  is  about  the  same  size  as  the  50nim 
finder  on  the  Leica,  with  the  exception  that  it  covers  the  35mm  lens  field. 
Leica  users  will  find  this  Wide  Angle  Finder  very  useful  when  the  35mm 
lens  is  to  be  used  a  great  deal,  because  the  camera  and  additional  view 
finder  can  easily  be  slipped  into  a  pocket  when  not  in  use. 

Rasuk  Direct  Vision  View  Finder 

A  non-optical  direct  view  finder,  known  as  the  Rasuk,  is  recommended 
for  certain  types  of  sport,  newspaper,  theatre,  and  general  pictures.  This 

finder  consists  of  a  rotating  metal  masking  frame 
and  a  peep  sight  for  centering  the  images.  A 
removable  reducing  mask  is  used  with  the  105mm 
and  135mm  lenses.  When  this  mask  is  removed 
the  frames  cover  the  fields  of  view  included  in  the 
35mm,  50mm,  73mm,  and  90mm  lenses. 

Fig.  27    Direct  Vision   Frame 
Finder  Attached  to  Leica. 

The  rear  peep  sight  has  a  small  rectangular  opening  for  use  with  all 
lenses  except  the  105mm  and  the  135mm  lenses.  A  small  round  peep  sight 
is  moved  into  position  for  using  the  Rasuk  Finder  with  these  105mm  and 
135mm  lenses. 


Leica  Equipment 

The  rear  sighting  frame  can  be  slightly  raised  or  lowered  for  obtain- 
ing the  proper  parallax  adjustments.  There  are  three  engraved  marks  of 
3%,  7,  and  oo  (infinity).  For  close-up  pictures  between  3%  and  7  feet 
the  parallax  adjustment  is  quite  necessary  in  order  to  include  the  exact 
field  of  view.  Leica  users  who  wear  glasses  may  find  this  finder  of  spe- 
cial value  as  it  may  be  a  little  easier  to  follow  the  objects  and  properly 
frame  the  picture.  With  a  little  practice  both  eyes  may  be  left  open 
when  the  Easuk  Finder  is  in  use.  This  is  of  particular  value  when  fol- 
lowing a  fast  moving  object.  With  both  eyes  open  the  object  may  be  seen 
very  quickly  before  it  comes  into  the  field  of  view  for  photographing,  and 
thus  the  final  picture  will  be  taken  with  the  object  in  the  correct  position. 

Fig.  28  Adjustable     Fig.  29     Regular 

Lens  Shade.  Lens   Shade.  Fig.  30     Wintu  Angle  View  Finder. 

The  Wintu  Angle  View  Finder 

We  are  all  familiar  with  the  way  in  which  most  pictures  are  taken  by 
pointing  the  camera  directly  towards  the  subject  with  the  operator  also 
facing  in  the  same  direction.  By  using  the  Wintu  Angle  View  Finder  the 
conventional  picture  taking  methods  are  abandoned  with  the  Leica  held  at 
a  right  angle  to  the  direction  in  which  the  operator  is  facing.  In  other 
words,  you  can  take  the  picture  around  a  corner  and  not  attract  attention 
or  have  the  people,  to  be  included  in  the  picture,  assume  unnatural  poses 
or  expressions.  This  finder  is  also  of  particular  value  for  making  candid 
camera  pictures. 

To  mount  the  Angle  View  Finder  on  the  Leica  it  is  only  necessary  to 
slip  the  metal  bracket  into  the  clip  on  top  of  the  Leica,  then  move  the 
small  angle  prism  over  the  range  finder  eye-piece.  By  sighting  through 
the  small  angle  prism  the  object  can  be  quickly  focused  when  using  the 
Model  D  or  F  Leica  with  the  built-in  range  finder.  After  focus  is  secured 
shift  the  eye  to  the  eye-piece  of  the  Angle  View  Finder. 

There  is  also  an  Angle  View  Finder  (Winko),  without  the  angle  prism, 
for  use  with  the  Leica  Models  A,  C,  and  E.  With  a  little  practice  an 
Angle  View  Finder  will  be  of  great  value  to  the  traveler,  candid  camera 
worker,  and  the  general  photographer. 

Sunshades  and  Their  Use 

Whenever  possible  it  is  advisable  to  use  a  sunshade  or  lens  hood  on 
the  Leica  lenses.  Such  protection  eliminates  any  possibility  of  stray  light 
from  entering  the  lens  and  thus  causing  a  slight  halation  on  the  film. 
This  fact  is  true  of  any  photographic  lens,  and  the  larger  the  aperture 
the  more  important  it  is  to  use  a  lens  shade  to  cut  off  the  strong  side  lights 
which  have  no  photographic  value. 


There  are  numerous  lens  shades  available  for  the  Leica  camera. 
Leitz  produces  a  small  metal  sunshade  for  the  35mm  and  50mm  lenses. 
An  adjustable  shade  is  made  for  the  longer  focal  length  lenses,  with  the 
exception  of  the  73mm  and  105mm  lenses  which  are  already  supplied  with 
their  own  shades.  This  adjustable  shade  has  engraved  markings  for  each 
focal  length,  and  the  proper  setting  is  quickly  made. 

Correction  Lenses  for 

Range  Finder  and  View  Finder 

Persons  who  wear  eyeglasses  find  it  difficult  at  times  to  focus  with  the 
aid  of  the  range  finder  or  to  see  the  entire  field  in  the  view  finder,  because 
the  eyeglasses  prevent  them  from  placing  their  eyes  close  to  the  camera. 
This  difficulty  can  be  overcome  by  the  use  of  special  Correction  Lenses  on 
the  eye  lenses  of  both  the  range  finder  and  view  finder. 

The  Correction  Lenses  embody  the  same  correction  as  that  contained 
in  the  eyeglasses  worn  by  the  Leica  user.  When  these  special  lenses  are 
placed  both  on  the  view  finder  and  the  range  finder,  it  is  not  necessary  to 
wear  eyeglasses  and  the  eye  can  be  placed  close  to  the  camera.  The  Leitz 
Co.  has  in  stock  the  necessary  Correction  Lenses  to  correct  nearsightedness 
and  far-sightedness  (myopia  and  hyperopia).  It  is  but  necessary  to  obtain 
the  prescription  of  one's  eyeglasses  from  the  optician  or  optometrist  and 
the  proper  Correction  Lenses  will  be  supplied.  These  screw  into  the  eye 
lenses  of  both  the  range  finder  and  the  view  finder. 

Special  lenses  to  correct  astigmatism  are  also  obtainable.  However, 
it  is  necessary  to  secure  them  on  special  order.  In  this  case  the  prescrip- 
tion for  the  eyeglasses  must  also  be  furnished. 

When  to  Use  the  Wire  Cable  Release 

When  making  either  time  or  instantaneous  exposure  the  Wire  Shutter 
Release  is  of  special  value.  For  example,  this  release  is  indispensa- 
ble for  making  exposures  in  photomicrography,  all  types  of  close-up  copy 
work,  and  wherever  exposures  are  to  be  made  where  it  is  essential  not  to 
jar  the  camera.  The  Wire  Release  is  screwed  over  the  release  button  of 
the  Leica  after  the  metal  protective  bushing  has  been  unscrewed. 

When  it  is  advisable  to  operate  the  Leica  at  a  distance  of  10  or  20 
feet  the  longer  corresponding  wire  releases  are  recommended.  For  exam- 
ple, the  20  foot  release  may  be  used  to  release  the  Leica  shutter  after  the 
camera  has  been  set  to  photograph  a  bird  or  possibly  when  the  photogra- 
pher wishes  to  be  included  in  the  picture. 

Slow  Timing  Device 

Owners  of  the  Leica  Models  A,  C,  E,  and  D  may  adapt  their  cameras 
to  the  slower  shutter  speeds  between  l/20th  and  1  second  by  using  the 
Slow  Timing  Device.  As  it  is  cheaper  to  secure  one  of  these  attachments 
than  to  have  these  earlier  Leica  models  converted  to  the  Model  F,  there 
is  a  definite  advantage  in  using  one  of  these  Slow  Timers. 

This  Slow  Timing  Device  is  screwed  directly  to  the  release  button  of 
the  Leica.  To  operate:  wind  the  shutter  of  the  Leica  and  set  the  shutter 
speed  dial  to  Z  the  same  as  for  a  time  exposure.  Next,  set  the  Slow 
Timer  by  turning  the  two  knobs  of  the  Timer  clockwise  until  the  dial  comes 
to  a  stop.  To  set  for  the  proper  speed  lift  the  longer  part  of  the  metal 
band  slightly  and  turn  back  or  forth  until  the  index  line  at  its  outer  edge 
points  toward  the  speed  required. 


Leica  Equipment 

The  shutter  is  released  by  pressing  the  release  button,  located  on  the 
side  of  the  Timer,  either  with  the  finger  or  a  Wire  Release.  Press  the 
release  down  slowly  and  hold  the  finger  there  until  the  shutter  lias  opened 
and  closed,  in  order  to  avoid  shaking  the  camera  during  the  short  moment 
when  the  shutter  is  open. 

On  some  of  the  older  cameras  the  release  button  varies  slightly  in 
height,  thus  it  may  be  necessary  to  make  a  slight  adjustment  on  the  Slow 
Timer  before  it  will  operate  correctly.  To  make  this  adjustment  simply 
use  a  screw  driver  and  turn  the  large  screw  head,  located  in  the  hollow 
shaft  of  the  Timer,  to  the  right  or  left  until  the  proper  release  is  secured 
If  the  release  button  of  the  camera  is  too  low  the  adjusting  screw  of  the 
Slow  Timer  may  not  have  sufficient  pressure  upon  the  shutter  release 
button... in  this  case  the  screw  is  turned  anti-clockwise.  If  the  button 
is  too  high,  the  rotating  levers  in  the  attachment  do  not  work  properly, 
consequently  the  shutter  opens  only  half  way  and  remains  open.  In 
such  a  case  the  adjusting  screw  is  turned  clockwise.  Once  the  proper 
adjustment  has  been  made  for  your  camera  the  Tinier  will  need  no  addi- 
tional change. 

Rapid  Winder 

There  are  many  occasions  when  the  Leica  user  may  wish  to  take 
successive  pictures  within  a  very  short  period  of  time  in  order  to  record 
continuous  actions.  The  Rapid  Winder  has  been  made  to  serve  this  pur- 
pose. With  this  attachment  extremely  interesting  picture  series  may  be 
made  of  dancers,  animals  at  play  or  running,  children,  wrestlers,  and 
rapidly  moving  objects  of  all  kinds. 

The  Leica  Rapid  Winder  replaces  the  base  plate  of  the  Leica  camera. 
A  trigger  is  pulled  after  each  exposure  is  made.  This  trigger  action 
causes  the  film  to  be  wound  and  the  shutter  set  at  the  same  moment. 
With  Leica  Cameras  from  serial  No.  1,  up  to  and  including  No.  111,449,  the 
small  pin  which  holds  on  the  base  plate  must  be  changed  to  a  larger  pin 
to  accommodate  the  Rapid  Winder  which  also  necessitates  a  new  base  plate, 
A  new  winding  spindle  and  winding  knob  must  also  be  supplied  as  these 
cameras  are  not  equipped  with  a  notched  winding  shaft.  Cameras  num- 
bering from  111,449  up  to  and  including  159,000  must  be  supplied  with  a 
new  winding  shaft  and  knob  for  the  shaft.  A  special  Rapid  Winder  for 
use  on  all  Leica  cameras  with  serial  numbers  below  159,000  is  available  in 
case  the  camera  is  not  to  be  changed. 

Fig.  32  New  type  Rapid  Winder 
with  trigger  action  which  fits  over 
base  of  Leica. 

Protective  Cases  for  Leica  Equipment 

All  Leica  equipment  should  be  kept  in  protective  cases  when  not  in 
use.  Such  protection  will  keep  your  equipment  looking  better  and  also 
prevent  the  camera  or  lenses  from  receiving  scratches  or  hard  knocks. 


Sand  and  dust  will  be  kept  out.  Too  much  emphasis  cannot  be  laid  upon 
the  importance  of  keeping  all  Leica  equipment  neatly  fitted  in  their 
proper  cases. 

There  are  Eveready  cases  for  the  camera  only.  Soft  leather  cases 
for  the  Camera  only  and  for  individual  lenses.  Then  there  are  a  number 
of  combination  cases  available  for  the  camera,  additional  lenses,  and  other 
extra  equipment  such  as  filters,  view  finders,  and  extra  film  magazines. 
All  color  filters  should  likewise  be  kept  in  soft  leather  cases  or  the  orig- 
inal filter  box  to  prevent  scratching  and  the  collection  of  dirt  on  the  glass 

Optical  Short  Distance 
Focusing  Device  "Nooky" 

This  new  and  ingenious  attachment  extends  the  usefulness  of 
the  automatic  focusing  principle  of  the  Leica  beyond  its  present 
range.  Heretofore  the  shortest  distance  for  which  the  setting  of 
the  lens  could  be  secured  automatically  was  3y2  feet.  By  Linscrew- 
ing  the  lens  from  the  camera  and  screwing  the  "Nooky"  into  its 
place,  and  subsequently  attaching  the  lens  by  its  lugs  to  it,  sharp 
focus  can  be  instantly  secured  on  all  objects  from  approximately 
40  inches  to  within  18  inches  of  the  camera. 

The  ""Nooky"  attachment  can  be  used  on  models  D,  F,  FF 
and  G  Leiea  Cameras.  It  is  intended  for  use  with  50mm  lenses  and 
as  this  issue  go-es  to  press,  it  is  available  for  the  Elmar  50mm  lens. 
Later  it  will  become  available  in  models  for  other  50mm  lenses. 

In  using  this  device  outdoors,  as  for  details  of  plants,  flowers 
and  insects,  one  should  focus  quite  critically  and  take  care  that  in 
shifting  the  eye  from  the  range-finder  to  the  view-finder  the  camera 
should  not  be  moved  out  of  focus.     "When  you  are  only  18  inches 
away  from  your  object  the  movement  of  an  inch  forward  or  back- 
ward makes  a  difference.     Outdoors  as  well  as  indoors  stop  down 
as  much  as  you  are  able  to  take  in  the  fullest  depth  possible,  and 
allow  for  any  error  in  focusing. 
A  framing  mask  is  incorpor- 
ated into  the  optical  range  finder 
part  of  this  device  which  ingeni- 
ously and  automatically  compen- 
sates for  the  shift  of  the  field  due 
to  parallax. 

At    the    short    distances    for 
which  this  attachment  is  intended 

Fig.  34  Optical  Short  Dis- 
tance Focusing  Device 


Leica  Equipment 

"Small  Print"  Manuel  Komroff 

Elmar  50mm  with   "Nooky"   2  sec.  f  :12.5   Panatomic  film—Harvey  Developer. 

the  depth  of  focus  is  obviously  very  small.  It  is  extremely  im- 
portant in  focusing  the  lens  to  employ  only  the  center  of  the  field 
measured  through  the  range  finder  when  the  double  edge  of  the 
framing  mask  enters  the  field  of  vision.  Unless  very  short  expos- 
ures are  called  for  due  to  inadequate  illumination  it  is  important 
to  stop  down  the  aperture  of  the  lens  to  at  least  f  :4.5  to  increase 
its  depth  of  focus.  The  following  table  gives  the  approximate 
depth  of  focus  at  the  various  settings  of  the  lenses  and  at  various 
distances  as  well  as  approximate  size  of  the  field  covered  at  the 
various  distances: 


Object  to  lens 


f:  3.5      4.5      6.3     9 

12.5        18     FIELD  COVERED: 








































16  14 





















Above  figures  are   rounded   off  to  nearest 


Single  Exposure  Leiccx 

Eecently  the  Single  Exposure  Leica  was  introduced  to  meet  the  demand 
for  making  single  negatives  instead  of  the  strip  of  exposures  on  the  ordi- 
nary roll^of  Leica  films.  This  camera  consists  of  a  small  housing  which  is 
the  exact  depth,  from  lens  flange  to  film  surface,  as  the  regular  Leica 
camera  models.  A  removable  ground  glass  plate,  film  holder,  and  one 
of  the  Leica  lenses  completes  the  outfit.  Some  of  the  advantages  and  uses 
of  this  camera  may  be  mentioned  as  follows: 

1.  Used  as  a  lens  tester.  The  distance  between  lens  flange  and  ground 
glass  is  28.8mm  which  is  exactly  the  same  as  the  distance  between  the 
lens  flange  and  film  surface  in  the  regular  Leica  models.  The  exact 
field  of  view  of  the  various  lenses  can  be  quickly  checked  by  focusing  the 
images  upon  the  ground  glass  of  the  single  Exposure  Camera. 

Fig.  35  Single  Exposure 
Leica.  Note  Film  Holder, 
View  Finder  and  Shutter. 

2.  For  use  in  photomicrography.     Single  micro  pictures  can  be  quickly 
made  with  this  camera  and*  developed  in  a  small  tray  either  for  testing 
exposure,  filters,  or  for  making  permanent  records.     Use  this  camera 
without  a  lens  but  with  a  6cm  extension  tube  between  the  Single  Ex- 
posure Leica  and  the  eyepiece  of  the  microscope,  with  a  black  cloth 
around  the  tube  to  exclude  stray  light.     The  camera  is  mounted  on  a 
rigid  support  beside  the  microscope.     Such  an  arrangement  makes  a 
very  inexpensive  photomicrographic  outfit,  and  insures  perfect  results. 

3.  As  a  copying  camera.    Any  type  of  copy  work  can  be  done  with  this 
Single  Exposure  Leica  by  using  an  adjustable  mounting  and  the  vari- 
ous extension  tubes  or  the  front  lenses.     If  desired,  it  is  possible  to 
obtain  various  fixed  distances  with  the  lens  which  can  later  be  shifted 
to  the  regular  Leica  for  making  pictures  on  the  longer  strip  of  film. 

4.  For  making  portraits.     It  is  quite  easy  to  compose  portraits  on  the 
ground  glass  of  this  camera  before  changing  to  the  film  holder  and 
making  the  exposure.    The  1.2cm  extension  tube  can  be  used  for  close 
ups  when  necessary.    If  one  of  the  50mm  lenses  is  used  the  collapsible 
feature  of  the  lens  barrel  can  be  adapted  to  obtaining  proper  focus. 

5.  Also  for  general  photography  where  only  one  picture  is  to  be  made 
at  a  time,  especially  where  it  is  necessary  to  test  exposures,  color  filt- 
ers, and  films  before  using  the  regular  Leica  camera. 

To  set  up  and  operate  the  Single  Exposure  Leica  proceed  as  follows: 

1.  Attach  the  camera  to  a  tripod,  Sliding  Arm  on  the  copy  attachment, 
or  any  other  rigid  support. 

2.  Screw  in  one   of  the  interchangeable   Leica  lenses   and  fit  the  Ibsor 

Lelca  Equipment 

shutter  over  the  front  of  any  lens  except  the  73mm  which  has  a  diam- 
eter larger  than  the  others.  If  the  Ibsor  shutter  does  not  fit  tightly, 
simply  press  down  the  cut  flange  until  a  tight  fit  is  secured  over 
the  lens. 

3.  Attach  the  wire   cable  release.     Usually  there  is   a   small   pin  which 
comes  attached  to  the  shutter;  this  is  used  for  making  exposures  by 
setting  the  shutter  and  inserting  the  pin  into  the   small  hole  on  the 
face  of  the   shutter,  and  then   removing  the   finger  from  the   shutter 
setting  lever.     The   shutter  remains   closed,  but  the  moment  the   pin 
is  withdrawn  the  shutter  will  open  and  close  at  the  proper  speed  setting. 
A  string  can  be  attached  to  the  pin  so  that  the  operator  can  easily 
get  into  his  own  picture  after  pulling  out  the  stop  pin  and  making  the 

4.  Next  see  that  the  ground  glass  is  clipped  into  position  with  the  ground 
side  of  the  glass  facing  toward  the  lens.    Then  secure  the  proper  focus 
by  moving  the  lens  mount  around  and  watching  the  image  on  the  ground 

5.  When  exact  focus  has  been  secured  replace  the  ground  glass  with  the 
single  film  holder.     Pull  out  the  dark  slide  covering  the  film.     Make 
certain  that  the  shutter  is  not  open  over  the  lens  while  withdrawing 
the  slide.    Then  make  the  exposure,  replace  the  slide,  and  remove  the 
film  holder. 

When  preparing  the  single  cut  films  for  this  camera  it  is  a  good  idea 
to  wind  the  35mm  film  in  an  opposite  direction,  with  the  emulsion  side  out, 
and  left  that  way  for  a  few  hours  or  several  days  before  using.  After  this 
treatment  it  will  be  found  that  the  filra  lies  much  flatter  and  it  is  easier 
to  cut  into  single  exposure  lengths.  It  is  also  advisable  to  cut  all  the  film 
required  at  one  time  and  keep  the  pieces  between  single  black  papers  in  a 
light-tight  box  or  envelope  until  used. 

Use  the  width  of  the  dark  slide  as  a  guide  for  cutting  each  individual 
film.  The  width  of  this  slide  is  the  exact  length  of  the  film  for  one  single 
exposure  in  this  camera. 

Devei0pment  of  these  single  films  can  be  carried  out  in  a  small  tray. 


Many  other  accessories  for  the  Leica  camera  will  be  described 
in  the  following  chapters.  There  are  also  many  circulars  giving 
directions  and  booklets  available  from  the  Leitz  Company  on  the 
various  Leica  attachments.  Directions  are  supplied  with  every 
accessory  when  purchased.  Therefore  the  greatest  emphasis  in  this 
book  has  been  laid  upon  the  actual  use  of  these  accessories.  The 
reader  is  invited  to  carefully  study  all  of  the  following  chapters, 
even  though  he  may  be  interested  in  only  one  or  two  subjects.  By 
reading  about  the  way  in  which  the  Leica  is  applied  to  other  uses,  it 
is  possible  to  pick  up  many  suggestions  which  can  be  applied  to  one's 
own  particular  field  of  Leica  photography.  Also  by  reading  these 
various  chapters  you  will  obtain  a  more  complete  idea  about  the 
scope  of  the  Leica  and  thus  be  able  to  understand  and  offer  sugges- 
tions to  your  Leica  associates  who  may  be  working  in  these  more  or 
less  specialized  fields  of  photography. 


Manuel  Komroff 

Harold  Harvey 



"What  kind  of  a  gadget  is  this?    Is  it  a  movie ?" 

"No,  it  is  a  little  camera.    Did  you  ever  hear  of  the  Leica?" 

"Oh  yes — so,  this  is  a  Leica;  it  certainly  is  a  compact  little 
thing!  How  large  a  picture  can  you  take  with  it?" 

"The  pictures  are  not  much  larger  than  a  postage  stamp;  but 
you  can  enlarge  them  to  almost  unbelievable  sizes. ' ? 

' '  Gee  whiz — it  must  have  a  marvelous  lens ! ' ' 

Why  does  everybody  think  at  once  of  the  lens  when  he  sees  a 
miniature  camera?  Why  must  a  small  camera  have  a  particularly 
good  lens?  What  properties  characterize  a  good  lens?  What  does 
the  lens  have  to  accomplish  and  how  well  does  it  succeed?  How  can 
you  use  your  lens  equipment  to  best  advantage  and  why  may  you 
want  to  have  several  lenses? 

When  miniature  photography  was  in  its  infancy,  there  were 
many  sceptics  who  pointed  out  that  an  enlargement  can  never  be 
as  sharp  as  a  contact  print;  and  since  the  small  negative  must  always 
be  enlarged  considerably,  the  loss  of  detail,  it  seemed,  ought  to  be 
so  great  that  the  enlargement  would  be  of  little  value. 

Practice  soon  gave  ample  proof  to  the  contrary.  But  practice 
alone  is  often  considered  as  insufficient  proof  because  you  may  have 
to  use  all  kinds  of  tricks  which  only  the  expert  knows.  To  set  our 
mind  at  ease  about  the  possibilities  of  miniature  cameras  we  may 
start  our  investigation  about  lenses  by  finding  out,  how  sharp  the 
negatives  of  miniature  cameras  are.  It  is  true  that  an  enlargement 
must  always  be  less  sharp  than  the  original  negative  because  the 
same  detail  is  stretched  over  a  larger  area.  Still  it  is  quite  possible 
that  we  may  not  be  able  to  detect  any  difference. 

Suppose  we  have  before  us  two  pages  covered  with  printed  mat- 
ter. Some  clever  printer  may  have  been  able  to  make  the  letters 
on  one  page  as  small  as  l/500th  of  an  inch.  But  the  second  page  may 
have  letters  as  small  as  l/1000th  of  an  inch.  We  hold  these  two 
pages  as  far  away  from  the  eye  as  we  would  hold  a  moderately  sized 
photograph.  Of  course,  we  would  not  be  able  to  read  these  pages. 


We  would  not  even  be  able  to  see  from  this  distance  which  of  the 
two  pages  has  the  smaller  letters. 

The  capacity  of  the  human  eye  to  make  detail  distinguishable 
or,  the  resolving  power  of  the  human  eye,  is  limited.  If  we  com- 
pare two  objects  as,  for  instance,  a  contact  print  and  an  enlarge- 
ment, the  former  having  detail  ten  times  smaller  than  the  resolving 
power  of  the  eye  and  the  latter  having  detail  which  is  only  three 
times  smaller  than  this  limit,  we  may  not  be  able  to  detect  any  dif- 
ference in  sharpness. 

The  limit  of  resolving  power  of  the  human  eye  has  been  deter- 
mined by  experiment  and  calculation.  It  is  customary  to  express 
it  by  the  magnitude  of  the  smallest  detail  In  the  object  which  cai 
still  be  resolved.  This  magnitude  depends,  of  course,  upon  the  dis- 
tance from  which  we  view  this  object.  If  we  want  to  see  finer  de- 
tail, we  move  the  object  closer  to  the  eye.  But  the  angle  of  vision 
under  which  the  finest  resolvable  detail  appears,  always  remains  the 
same.  Thus  it  has  been  found  that,  allowing  for  slight  variation  oJ 
individual  power  of  vision,  the  limit  of  resolving  power  of  the  human 
eye  is  about  2  to  3  minutes  of  arc.  That  means  that  in  an  objed 
held  about  ten  inches  from  the  eye  we  cannot  see  detail  if  it  is  closei 
together  than  l/100th  part  of  an  inch.  If  the  object  is  20  inches 
from  the  eye,  the  detail  must  be  2/100ths  of  an  inch  apart  if  we  are 
to  distinguish  it. 

Now  we  have  to  investigate  how  closely  the  detail  can  be  crowdec 
together  in  a  negative  from  a  miniature  camera.  This  investigation 
is  rather  involved  and  it  is  to  our  advantage  if  we  penetrate  more 
deeply  into  the  entire  process  of  the  formation  of  images  by  lenses 

Let  us  select  the  simplest  object  possible :  one  luminous  point 
Figure  38  shows  a  diagram  of  a  simple  experiment.  A  lentil-shapec 
piece  of  glass  is  placed  at  a  certain  distance  from  the  luminous  point  P 

A  sector  of  light  of  the  angular  aperture  a  passes  through  thi 
glass  and  in  doing  so  it  changes  its  original  direction.  Each  Hgfr 
ray  is  broken  or,  in  scientific  language :  refracted.  The  more  obliquely 
the  rays  meet  the  surface  of  the  glass,  the  more  pronounced  is  the 
change  in  direction.  By  skillfully  shaping  the  piece  of  glass  we  maj 
be  able  to  guide  each  ray  in  such  a  manner  that,  after  leaving  the 
lens,  the  entire  btgndle  of  rays  converges  as  a  cone  of  the  angulai 
aperture  b  until  the  rays  meet  again  in  one  single  point  Pa,  which  is 
the  image  of  the  original  point  P.*  This  is  the  essential  principle  oJ 

*  If  we  hold  a  screen  in  the  plane  I-I  we  see  on  it  one  bright  spot 


the  formation  of  a  real  image.  When  photographing  a  complex  ob- 
ject the  lens  collects  diverging  bundles  of  rays  from  each  object  point 
and  must  unite  them  in  image  points  which  must  have  such  location 
in  respect  to  each  other  that  they  reproduce  the  object  in  the  image 

Fig.  38     Formation  of  a  Real  Image  of  a  Luminous  Point 

It  is  the  job  of  the  lens  designer  to  skillfully  shape  the  lens.  In 
practice  this  job  is  so  immensely  difficult  that  we  may  say,  it  is  im- 
possible to  succeed  completely.  In  the  first  place  it  is  next  to  impos- 
sible to  grind  and  polish  accurately  enough  any  surfaces  of  unusual 
shape.  In  fact,  in  photographic  lenses  we  only  find  lenses  with 
spherical  or  plane  surfaces.  But  even  if  we  were  not  limited  in  this 
respect,  we  would  meet  with  many  other  difficulties.  These  light  rays 
are  tricky  individuals.  One  single  ray  of  white  light,  for  instance, 
upon  entering  the  lens,  begins  to  disintegrate  into  rays  of  various 
colors  and  finally  a  rainbow  colored  cone  of  light  leaves  the  lens. 
This  phenomenon  is  known  as  chromatical  aberration.  We  also  must 
contend  with  the  fact  that  if  we  use  spherical  lenses,  the  outsiders, 
the  rays  which  meet  the  lens  with  greatest  obliquity,  are  bent  too 
strongly  and  refuse  to  come  to  the  same  meeting  point  where  the 
rays  of  the  center  of  the  cone  unite.  This  is  known  as  spherical 

There  are  many  more  misbehaviors  of  light  rays  which  give  the 
lens  designer  a  headache.  If  he  wants  to  guide  these  rays  to  the 
same  point  he  cannot  restrict  himself  to  the  use  of  one  single  lens. 
He  must  combine  several  pieces  of  glass,  selecting  different  materials 
and  shapes  and  placing  them  at  accurately  determined  distances 
from  each  other.  Thus  he  creates  a  photographic  objective  of  the 
type  shown  in  figure  39  which  is  the  famous  Elmar  lens  of  the  Leica 

You  will  see  the  definite  plan  of  construction:  a  single  plano- 
convex lens  is  followed  by  a  biconcave  lens,  placed  at  a  definite  dis- 


tance  from  the  first.  Behind  this  second  element  there  is  a  pair  of 
lenses  cemented  together.  Each  lens  has  spherical  or  plane  surfaces 
which  in  a  diagram  appear  as  parts  of  circles  or  straight  lines.  The 
centers  of  all  these  circles  lie  on  one  straight  line,  called  the  optical 

Fig.    39      Cross-section    of 
Elmar  50mm  f  :3.5  Lens 


Fig.  40  Cross-section 
of  the  Hektor  73mni 
f  :1.9  Lens 

There  are  other  types  of  objectives*  such  as  the  Hektor  shown  in 
figure  40,  the  Summar  and  many  others.  Each  of  them  is  bnilt 
according  to  a  different  plan  and  represents  an  effort  to  make  the 
rays  behave,  but  no  effort  is  completely  successful.  There  is  always 
a  sacrifice  in  some  respect,  as  we  shall  see  later. 

With  one  of  these  objectives  we  may  perform  a  few  interesting 
experiments.  Of  course,  we  cannot  actually  select  as  an  object  one 
single  luminous  point.  But  we  may  produce  a  disc  of  light  of  a 
definite  and  small  diameter.  Suppose  a  ground  glass  is  placed  before 
a  bright  lamp  and  again  before  the  ground  glass  an  iris  diaphragm 
which  can  be  contracted  to  very  small  diameters.  Thus  we  may  pro- 
duce a  luminous  disc  of,  say  l/10th  of  an  inch.  We  place  the  lens 
at  a  certain  distance  from  the  light  source  and  on  the  other  side  of  it 
we  place  a  screen  so  that  on  it  the  image  of  the  luminous  disc  appears 

*  "At  this  place,  I  wish  to  emphasize  that  I  prefer  the  word  'objective' 
to  the  word  'lens',  although  the  latter  term  is  more  popular.  A  lens  is  really 
one  piece  of  glass  whereas  an  objective  is  a  compound  unit  and  consists  of 
several  lenses." 



with,  maximum  sharpness.  The  conditions  may  have  been  so  selected 
that  the  image  has  a  diameter  of  l/200th  of  an  inch.  In  other  words, 
the  image  is  twenty  times  smaller  than  the  object.  Now  we  reduce 
the  opening  of  the  iris  diaphragm  to  l/30th  of  an  inch  and  the  image, 
again  twenty  times  smaller,  is  l/600th  of  an  inch.  But  as  we  further 
reduce  the  diameter  of  the  luminous  disc  (perhaps  to  l/100th)  we 
find  that  the  image  retains  the  size  of  l/600th  inch. 

This  is  a  very  important  discovery.  Suppose  we  would  have 
two  luminous  object  points,  each  of  them  very  small,  for  instance 
1/lOOOth  of  an  inch  in  diameter,  but  less  than  l/30th  of  an  inch  apart. 
The  lens,  when  forming  the  image  at  the  same  ratio  of  reduction  as 
before,  (20:1)  reduces  the  distance  between  the  images  to  less  than 
l/600th  but  at  the  same  time  each  of  the  images  occupies  l/600th. 
The  two  image  discs  overlap,  melting  so  to  speak  into  each  other.  We 
have  now  overstepped  the  limit  of  resolving  power  of  the  lens. 

This  experiment  reveals  a  very  important  fact  regarding  the 
performance  of  optical  instruments :  the  image  of  a  theoretical  object 
point  is  never  a  point  but  a  light  disc  of  definite,  measureable 
diameter.  But  if  we  think  that  the  actual  magnitude  of  this  disc  can 
be  made  smaller  and  smaller  as  manufacturing  methods  and  the  art 
of  lens  designing  improves,  we  are  greatly  mistaken.  Unfortunately 
there  are  definite  limits  which  cannot  be  overstepped  and  they  have 
their  cause  in  the  very  nature  of  light  itself. 

In  a  diagram  we  may  indicate  a  light  ray  by  one  straight  line,  but  in 
reality  we  find  that  as  light  progresses  with  infinite  speed  in  the  direction 
of  this  line,  very  minute  vibrations  take  place  with  enormous  frequency. 
Physicists  have  attempted  to  explain  the  many  strange  phenomena  which 
light  can  produce,  by  assuming  that  it  propagates  like  a  wave  motion. 
To  help  our  imagination  we  may  make  a  comparison.  Suppose  that  you 
throw  a  stone  into  a  lake.  From  the  center,  where  the  stone  hits  the 
surface  of  the  water,  we  see  a  wave  motion  spreading  with  equal  speed  in 
every  direction  as  circles  of  ever  increasing  diameter.  From  crest  to  crest 
of  successive  waves  there  is  always  the  same  distance,  called  the  wave 
length.  This  wave  length  may  be  small  or  large.  The  motion  of  the 
waves  probably  spreads  with  a  speed  of  several  feet  or  yards  a  second. 
But  as  these  waves  move  away  from  the  center,  the  surface  of  the  water 
only  moves  up  and  down  so  that  if  a  piece  of  wood  is  swimming  on  the 
water,  it  is  carried  up  and  down  but  not  away  from  the  center  of  the  dis- 

If  light  proceeds  from  a  luminous  point,  waves  of  unbelievably  small 
wave  length  spread  with  equal  speed  in  every  direction.  This  speed,  how- 
ever, is  very  great,  almost  200,000  miles  per  second.  The  vibrations  take 
place  at  right  angles  to  the  direction  of  propagation.  And,  to  come  back 
to  the  formation  of  the  image  of  a  point,  where  the  light  is  concentrated 
into  the  image  point,  we  find  an  enormous  confusion  of  vibrations  from 
light  waves  of  different  lengths  and  directions.  These  waves  partly  inter- 
fere with  and  cancel  each  other  but  still  they  spread  the  light  over  a 


certain  area.  In  fact,  if  we  would  study  this  area  through  a  microscope, 
we  would  find  a  small  disc  of  light  surrounded  by  rings  of  light  of  very- 
weak  and  rapidly  diminishing  intensity.  This  is  called  a  diffraction  pattern. 

We  need  not  penetrate  further  into  these  theoretical  optical  matters. 
We  must  only  realize  that  even  a  theoretically  perfect  objective  has  a  lim- 
ited resolving  power.  This  theoretical  resolving  power  depends  mainly  upon 
the  angle  of  convergence  of  the  cone  of  light  which  the  lens  concentrates  (in 
fig.  38  this  cone  is  marked  6).  The  larger  this  angle,  the  smaller  is  the  finest 
detail  which  a  theoretically  perfect  objective  could  reveal. 

But  here  we  can  see  the  difference  between  theory  and  practice.  It 
is  unfortunate  but  true  that,  as  we  try  to  make  objectives  with  great  light 
concentrating  power,  the  difficulties  which  we  encounter  increase  beyond 
description.  These  misbehaviors  of  light:  spherical  and  chromatical  aber- 
ration and  many  others,  can  hardly  be  held  in  check.  If  we  are  content 
with  a  small  cone  of  light,  the  situation  can  be  controlled  quite  nicely.  A 
small  cone,  of  course,  contains  so  to  speak,  only  a  small  amount  of  light 
and  when  photographing  we  would  have  to  give  very  long  exposures.  In 
this  age  of  speed  this  would  be  a  serious  handicap.  Therefore  there  is  a 
constant  race  between  the  manufacturers  to  produce  lenses  of  greater  light 
concentrating  power:  but  the  task  before  them  is  very  difficult  indeed. 
The  Iris  Diaphragm  and  the  Resolving  Power 

As  you  know,  photographic  lenses  are  equipped  with  iris  dia- 
phragms with  which  the  angular  aperture  of  the  cone  of  light,  and 
therefore  also  the  light  intensity  in  the  plane  of  the  image,  can  be 
regulated.  As  we  open  or  close  this  diaphragm  the  difference  be- 
tween theory  and  practice  evidences  itself  as  follows: 

a.  "When  the  iris  diaphragm  is  closed,  the  difference  between  theory 
and  practice  is  least  noticeable.    At  the  same  time  the  theoretical 
resolving  power  is  at  its  worst. 

b.  As  the  iris  diaphragm  is  gradually  opened,  the  practical  insuffi- 
ciencies come  more  and  more  into  the  foreground.    This  does  not 
mean  that  any  practically  produeeable  lens  yields  the  sharpest 
images  when  the  iris  diaphragm  is  closed.    In  fact,  in  a  good  lens 
the  sharpness  will  increase  as  we  begin  to  open  the  iris.    Only, 
it  will  not  increase  as  much  as  can  be  theoretically  expected. 

c.  If  the  iris  diaphragm  is  opened  considerably,  the  misbehaviors  of 
light  finally  become  so  noticeable  that  even  the  actual  sharpness 

A  good  method  to  judge  the  quality  of  a  lens  is,  therefore,  to  find 
out  how  much  the  iris  can  be  opened  with  a  beneficial  effect  upon  the 
sharpness,  the  resolving  power,  of  the  lens. 

Every  photographer  should  realize  the  full  significance  of  this 
fact  and  should  not  believe  the  wrong  statement  that  any  lens  per- 
forms best  when  the  iris  is  closed  as, far  as  possible. 

But  let  us  not  forget  our  original  question:  How  sharp  is  a 
miniature  negative?  The  actual  limit  of  the  resolving  power  is  not 



the  only  factor  to  consider.  We  must  not  forget  that  the  image  which 
the  lens  has  formed  is  recorded  on  the  film,  which  is  coated  with  a 
light-sensitive  emulsion.  The  emulsion  is  turbid  and  has  a  certain 
thickness.  As  the  light  penetrates  into  the  emulsion,  it  is  scattered 
and  the  record  of  the  image  of  one  single  luminous  point  upon  the 
film  emulsion  will  necessarily  occupy  a  larger  area.  Thus  the  film 
emulsion  introduces  a  certain  loss  of  sharpness.  If  we  wish  to  find 
a  quantitative  measure  for  the  sharpness  of  a  minature  negative  we 
must  measure  the  diameter  of  the  image  disc  on  the  emulsion  when 
the  object  is  so  small  that  its  image  is  equal  to  the  limit  of  resolving 
power  of  the  lens.  This  area  is  often  referred  to  as  the  circle  of  con- 
fusion, because  within  this  circle  there  is  a  great  confusion  of  aber- 
rations, diffractions,  dispersions  and  many  other  misbehaviors  of  light. 

Thus  it  has  been  found  that  the  diameter  of  the  circle  of  con- 
fusion of  the  better  lenses,  such  as  are  used  in  miniature  cameras, 
does  not  exceed  l/800th  of  an  inch,  even  when  the  diaphragm  is  open 
and  the  practical  discrepancies  are  most  apparent.  Upon  closing  the 
iris  diaphragm,  the  sharpness  improves,  then  retains  this  optimum 
value  until  finally,  as  the  aperture  assumes  very  small  values,  it  de- 
creases slightly. 

"We  learned  in  the  beginning  that  the  smallest  detail  which  the 
human  eye  can  detect  from  a  distance  of  10  inches  is  about  l/100th 
of  an  inch.  If  the  detail  in  a  miniature  negative  is  crowded  into  as 
small  a  spot  as  l/800th  it  is  quite  evident  that  this  negative  can  be 
enlarged  8  times  without  noticeable  loss  of  sharpness. 

If  you  really  want  to  look  at  the  picture  you  will  never  hold  an 
enlargement  of  8  x  10  inches  closer  than  10  inches  from  the  eye.  Only 
grain  fiends  have  a  habit  of  smelling  their  pictures,  regardless  of 
size.  We,  who  want  to  enjoy  the  pictures  which  we  have  taken,  have 
learned  that  an  enlargement  may  appear  as  sharp  as  a  contact  print 
and  thus  we  may  confidently  discard  bulky  equipment  in  favor  of  the 
small  and  compact  Leica.  Its  existence  is  built  upon  a  sound  scientific 
basis  and,  as  far  as  sharpness  of  the  picture  is  concerned,  we  may 
safely  say  that  for  our  purposes  it  is  sufficiently  equivalent  to  the 
large  camera. 

The  Miniature  vs  Larger  Cameras 

With  this  fact  established  we  shall  now  proceed  to  find  that  in 
other  respects  the  minature  camera  is  definitely  and  considerably 
superior  to  the  large  camera.  Above  all,  it  has  reconciled  two  oppos- 
ing factors  which  cannot  be  mastered  with  larger  cameras :  speed  of 
the  lens  and  depth  of  focus  in  the  negative. 


You  will  often  have  found  in  photographs  that  some  parts  of  the 
picture  were  sharper  than  others.  Either  the  objects  close  to  the 
camera  are  sharp  and  those  further  away  appear  fuzzy;  or  the  back- 
ground is  sharp  and  the  foreground  is  out  of  focus;  or  there  is  a 
range-in-between  which  is  imaged  crisply,  whereas  the  very  near  and 
very  far  objects  lack  in  sharpness.  The  photographer  can,  at  will, 
select  the  range  of  object  distances  within  which  everything  is  imaged 
with  the  best  possible  sharpness  and,  if  he  uses  his  camera  correctly, 
he  can  always  direct  the  attention  of  the  spectator  to  the  subject  of 
interest.  There  is,  then,  a  range  within  which  everything  is  equally 
sharp  and  this  range  represents  the  depth  of  focus. 

In  photographs  of  general  outdoor  scenes  and  many  other  types  of 
pictures  it  is  highly  desirable,  if  not  essential,  that  the  entire  picture  be 
in  perfect  focus.  Only  in  portraits  and  group  pictures  it  often  is  of  spe- 
cial advantage  to  reproduce  in  sharpest  focus  only  the  subject  of  interest 
and  to  have  foreground  and  background  intentionally  out  of  focus,  in  order 
not  to  distract  the  attention  of  the  spectator. 

If  you  compare  Leica  snapshots  with  those  of  a  larger  camera,  you 
will  notice  at  once  the  increased  depth  of  focus  in  the  Leica  enlargement. 
I  used  the  word  snapshots  for  a  special  reason  because  as  long  as  the  big- 
camera  owner  is  allowed  to  increase  the  time  of  exposure  of  his  photos  as 
much  as  he  wants,  he  can  also  produce  pictures  of  remarkable  depth  of 
focus.  He  must  only  close  the  iris  diaphragm. 

On  the  mount  of  a  photographic  lens  a  whole  series  of  numbers  is  en- 
graved which,  upon  first  sight,  seem  to  have  no  sensible  relation  to  each 
other.  But  if  in  a  competition  between  large  and  small  camera  the  iris 
diaphragm  is  in  both  cases  set  to  the  same  figure,  for  instance  f  :4.5,  and 
then  the  two  pictures  are  compared  in  regard  to  depth  of  focus  you  will 
win  the  race  by  a  wide  margin  if  you  were  the  one  who  used  the  miniature 
camera.  And  if  you  had  inquired  from  your  competitor  about  the  time 
of  exposure  of  his  picture,  you  would  have  found  out  that  it  was  the  same 
as  that  which  you  gave,  provided  you  both  gave  the  correct  time. 

In  other  words,  the  iris  diaphragm  affects  not  only  the  depth  of  focus 
but  also  the  time  of  exposure.  It  seems  important  to  study  both  functions. 
We  begin,  of  course,  with  the  effect  upon  the  depth  of  focus.  But  even 
before  we  comedo  this,  we  must  explain  why  the  large  camera,  when  the 
iris  diaphragm  was  set  to  the  same  figure,  yielded  images  of  less  depth 
of  focus. 

Depth  of  Focus  and  Relative  Aperture 

We  resort  again  to  experiments.  "We  take  a  lens  for  a  5  x  7  inch 
camera  and  the  Elmar  50mm  lens.  In  both  eases  we  set  the  iris  to 
the  figure  f  :4.5  although  we  do  not  know  as  yet  what  that  means.  We 
also  need  two  screens,  on  which  to  project  the  images  and  a  yardstick 
ruled  in  very  fine  units,  with  which  we  want  to  measure,  not  only  the 
distance  between  screen  and  lens,  but  also  the  size  of  the  images  on  the 





Fig.  41    Fields  Covered  by  Six  Different  Leica  Lenses.    All  Photographs 
Made  From  the  Same  Point 


Since  we  want  to  explore  various  ranges  of  object  distance,  we 
select  at  first  an  object  which  is  very  very  far  away:  the  sun.  We 
move  the  screens  back  and  forth  behind  the  lenses  until  the  images 
are  as  sharp  as  possible.  "We  see  in  both  cases  a  very  small  and  very 
brilliant  spot.  The  screen  for  the  large  lens  is  about  10  inches  behind 
the  larger  lens,  whereas  the  other  one  is  about  2  inches  behind  the 
Blmar  lens. 

This  distance  at  which  the  image  of  an  infinitely  distant  object 
is  formed,  is  called  focal  length  of  the  lens*  If  we  have  held  the 
lenses  so  that  their  optical  axes  pointed  directly  into  the  sun,  the 
images  are  formed  in  the  focal  points.  The  screens  are  in  the  focal 
planes  of  the  respective  lenses. 

The  focal  length  of  a  lens  is  a  very  important  factor.  It  deter- 
mines the  location  and  size  of  the  images  which  the  lens  forms 
of  objects  at  different  distances,  the  depth  of  focus,  the  perspective 
and  many  other  things  and  is  one  of  the  main  keys  to  the  secret  of  the 
performance  of  the  lens. 

A  comparison  of  the  sizes  of  the  images  which  in  our  experiment 
both  lenses  have  formed  of  the  sun  reveals  that,  although  both  of  thenj 
are  very  small,  yet  the  one  formed  by  the  Elmar  is  still  the  smaller 

From  the  experiment  we  learn  that  the  image  of  an  infinitely  far 
object  is  formed  in  the  focal  plane  and  that  the  lens  with  the  smaller 
focal  length  forms  the  smaller  image. 

Now  let  us  select  another  object  which  is  nearer,  for  instance  a, 
telegraph  pole  which  is  about  30  feet  high  and  100  feet  away.  We 
discover  that  the  screens  must  be  moved  farther  away  from  the  lens 
in  order  to  be  in  the  plane  of  the  image.  When  the  screens  are  prop- 
erly focused  the  one  of  the  10  inch  lens  is  0.084th  of  an  inch 
(or  2.12mm)  behind  the  focal  plane.  Had  we  left  it  in  the  focal 
plane,  the  image  would  have  been  anything  but  sharp.  The  size  of 
the  image  of  the  pole,  incidentally,  is  about  3  inches  high. 

The  screen  of  the  Blmar  lens,  however,  had  to  be  moved  only 
0.0033th  of  an  inch  (or  0.085mm).  This  is  not  much  more  than  the 
thickness  of  a  sheet  of  paper.  Therefore  it  is  not  surprising  that  even 
as  long  as  this  screen  was  left  in  the  focal  plane,  the  image  was  still 
remarkably  sharp.  As  to  the  size  of  the  image  of  the  pole,  which  the 
Elmar  has  formed,  it  is  only  5/8th  of  an  inch  high. 

*  Actually  the  focal  length  is  the  distance  of  the  focal  point  from  the 
so-called  principal  plane.  Readers  interested  in  optics  may  find  further 
Information  in  physics  textbooks. 



This  experiment  will  convince  you  that  the  Elmar  lens  of  the 
Leiea  camera  forms  images  of  greater  depth  of  focus.  The  image  of 
the  sun  (many  millions  of  miles  away)  was  practically  in  the  same 
plane  as  that  of  the  telegraph  pole  which  was  only  100  feet  from  the 
lens.  But  now  remember  figure  38  where  the  rays  coming  from  one 
object  point  converge  to  a  small  spot  and  then  diverge.  As  you  move 
the  screen  farther  away  from  the  lens,  the  rays  from  this  object  point 
occupy  a  larger  and  larger  area.  At  the  same  time  the  cone  of  rays 
from  a  nearer  object  point  would  still  be  in  the  process  of  converging. 
You  must  also  remember  that  the  image  which  a  lens  forms  of  a  point 
even  in  the  plane  of  maximum  sharpness  is  never  a  true  point  but  a 
small  disc  (circle  of  confusion).  Thus  we  can  illustrate  the  entire 
situation  in  a  diagram  shown  in  figure  42. 

Fig.  42     Depth  of  Focus  "with  Iris  Diaphragm  Open 

Fig.  43     Depth  of  Focus  with  Iris  Diaphragm  Closed 
Point  P  is  imaged  at  P3  where  the  image  occupies  a  circle  of  confu- 
sion of  the  diameter  A — B.    Point  Pw  nearer  to  the  lens,  is  imaged 
farther  away  so  that  in  the  plane  I— I  the  rays  are  still  as  far  apart 

as  A B.    The  geometrically  correct  plane  of  the  image  of  point  P! 

is  farther  away,  at  P4. 

On  the  other  hand,  point  P2,  farther  away  from  the  lens  than 
P  is  imaged  closer  than  P3  and  in  the  plane  I-I  .the  rays  have  diverged 
so  much  that  they  occupy  the  area  A — B.  The  total  effect  is  that 
on  the  film  held  in  the  plane  I — I  the  images  of  all  three  points  are 
equally  sharp  and  as  sharp  as  the  limit  of  resolving  power  of  the 


If  you  have  understood  this  relation,  you  will  be  able  to  answer 
the  question:  what  happens  when  the  iris  diaphragm  is  closed  fur- 
ther? The  angular  aperture  of  the  image-forming  cones  of  rays 
becomes  smaller  and  the  rays  converge  and  diverge  less  rapidly.  Thus 
the  depth  of  focus  increases.  This  is  shown  in  the  diagram  of 
figure  43. 

To  summarize:  Lenses  of  shorter  focal  length  have  greater  depth  of 
focus.  The  depth  of  focus  of  a  lens  of  given  focal  length  increases  when 
you  close  the  iris  diaphragm. 

Depth  of  Focus  Scale 

As  mentioned  before  we  find  on  the  lens  mount  a  scale  with,  numbers, 
the  meaning  of  which  we  have  not  yet  explored.  All  we  know  is  that  these 
numbers  refer  to  different  apertures  of  the  iris.  But  at  the  base  of  the 
lens  mount,  there  is  a  beveled  ring  on  which  from  one  center  index  mark 
to  both  sides  we  find  the  same  numbers  as  on  the  iris  scale.  These  numbers, 
in  connection  with  the  distance  scale  on  the  lens  ring  enable  you  to  read 
the  depth  of  focus  for  each  aperture  of  the  iris. 

You  can  close  the  iris  to  the  mark  f  :4.5,  focus  the  lens  to  an  object 
which  is  20  feet  away  and  the  depth-of-focus  scale  informs  you  that  now 
even  objects  as  close  as  14%  and  as  far  as  32  feet  are  in  perfect  focus. 

If  you  make  intelligent  use  of  this  depth-of-focus  scale,  you  can  greatly 
enhance  the  quality  of  your  pictures.  It  is  not  always  advisable  to  have  the 
greatest  depth  of  focus  possible.  In  a  portrait,  for  instance  fine  effects  can 
be  obtained  by  intentionally  reducing-  the  depth  of  focus,  so  that  everything 
except  the  features  of  the  subject  is  out  of  focus.  Thus  the  attention  of  the 
spectator  is  at  once  directed  to  the  subject  of  interest. 

Even  in  other  cases  you  can  make  good  use  of  the  scale.  If  on  your 
honeymoon  you  want  to  take  a  picture  of  your  bride  at  Niagara  Falls  you 
might  be  equally  interested  in  showing  the  beauty  of  the  falls.  If  you  set 
the  iris  to  f  :9  and  your  bride  is  15  feet  from  the  camera  which  is  correctly 
focused  for  this  distance,  everything  from  9*/£  to  35  feet  is  in  focus  but  the 
falls  which  are  farther  away,  are  not  sharp.  But  if  you  consult  the  depth- 
of-focus  scale  you  may  learn  that  with  the  iris  at  the  same  stop,  the  same 
distance  from  the  camera  to  the  bride  but  the  focusing  mount  set  to  a  dis- 
tance of  27  feet  everything  from  12%  feet  to  infinity  is  sharp.  You  have 
sacrificed  the  foreground  for  the  benefit  of  the  background.  Many  photog- 
raphers do  not  realize  the  full  significance  of  this  possibility  to  correctly 
"place"  the  range  of  depth  of  focus. 

At  this  place  it  is  advisable  to  draw  attention  to  the  fact  that  the 
depth-of-focus  scale  should  not  be  taken  too  literally.  You  must  realize 
that  the  smaller  the  circle  of  confusion, — or  to  express  it  differently,  the 
sharper  the  image  or  the  better  the  correction  of  the  lens, — the  smaller  is 
the  range  of  depth  of  focus  for  a  given  aperture.  The  scales  are  mostly 
based  on  an  assumed  size  of  this  circle  of  confusion  which  is  still  small 
enough  to  permit  enlargements  to  about  8  x  10  inches.  It  was  mentioned 
before  that  upon  closing  the  iris,  the  actual  resolving  power  increases. 
Quite  a  number  of  other  factors,,  such  as  the  thickness  of  the  emulsion  on 
the  film,  etc.,  have  to  be  considered.  Therefore,  the  actual  range  of  maxi- 
mum sharpness  (especially  at  smaller  aperture  of  the  iris)  is  not  identical 
with  the  depth  of  focus  indicated  on  the  scale  although  even  within  this 
latter  range,  the  sharpness  is  still  satisfactory. 



If  on  the  other  hand  your  best  friend  wants  to  get  your  goat  by  boast- 
ing that  his  lens  of  the  same  focal  length  and  the  same  aperture  has  a 
greater  depth  of  focus,  don't  be  jealous,  just  pity  him  because  either  he  lies 
or  he  admits  with  his  boast  that  his  lens  is  not  as  well  corrected  as  yours. 

Thus  we  conclude  our  investigation  regarding  the  depth  of  focus 
and  direct  our  attention  to  the  other  function  of  the  iris  diaphragm: 
The  regulation  of  the  amount  of  light  which  passes  through  the  lens. 

Exposure  Variations 

It  is  quite  easy  to  comprehend  that  if  we  close  the  iris  diaphragm, 
less  light  passes  through  the  lens.  But  this  knowledge  alone  is  of 
little  help  to  us.  Suppose  we  had  to  close  the  iris  to  one-half  of  its 
original  aperture  in  order  to  have  enough  depth  of  focus  in  the  pic- 
ture; how  much,  do  we  have  to  increase  the  exposure?  Bather  than 
try  until  we  hit  by  accident  the  right  time  of  exposure,  let  us  analyse 
the  situation.  Figure  44  helps  us  in  our  investigation. 

Fig.  44     Principle  of  "Relative  Aperture" 



Four  rays,  marked  I  to  IV  come  from  a  distant  point.  If  the  iris 
diaphragm  is  fully  open,  the  entire  amount  of  light  between  the  rays 
I  and  IV  is  collected  by  the  objective.  But  the  diagram  shows  only 
a  cross  section  of  the  lens.  Actually  these  rays  would  fill  an  area 
represented  by  the  circle  No.  1  at  the  left  side  of  the  diagram. 

If  we  close  the  iris  diaphragm  to  one-half  of  its  original  diameter 
only  light  within  the  cone  of  the  rays  II  to  III  filling  the  area  of  the 
circle  No.  2  would  be  able  to  pass  through  the  lens.  Although  this 
circle  has  one-half  the  diameter  of  that  of  No.  1,  you  will  remember 
that  the  area  decreases  with  the  square  of  this  ratio.  Thus  only  one- 
quarter  of  the  original  amount  of  light  passes  through  the  lens  when 
the  iris  diaphragm  is  closed  to  one-half.  Closing  it  further  to  l/3rd 
of  its  original  aperture  would,  of  course,  reduce  the  intensity  to 
l/9th,  etc. 


Bealizing  this  we  could  make  a  scale  which  carries  the  number 
1  when  the  iris  is  fully  open,  number  4  when  the  iris  is  closed  one- 
half;  number  9  when  it  is  closed  to  l/3rd,  etc.  These  numbers  would 
indicate  the  increase  in  exposure  necessary  when  the  iris  is  partly 
closed.  But  this  would  not  fully  solve  our  problem.  Suppose  you 
want  to  compare  your  Elmar  with  the  lens  of  your  old-fashioned 
competitor  with  the  5  x7  camera.  His  lens  has  a  much  larger  diam- 
eter. Does  it  collect  more  light  when  the  iris  diaphragm  is  fully 
open?  Comparative  exposure  data  may  show  that  even  with  the  iris 
so  far  open  that  the  actual  diameter  of  the  cone  of  light  entering 
his  lens  is  twice  that  of  your  lens,  he  requires  longer  exposures. 
What  we  need  is  an  absolute  system  so  that  we  can  compare  the  light 
transmitting  power  of  lenses  of  different  focal  lengths. 

Do  not  forget  that  the  lens  of  the  5x7  inch  camera,  having  a 
focal  length  of  10  inches,  also  forms  relatively  larger  images.  If  for 
instance  a  lens  of  different  focal  length  has  twice  the  diameter  of 
your  Elmar  but  objects  at  identical  distances  are  imaged  twice  as 
large,  the  greater  amount  of  light  passing  through  the  larger  lens  is 
also  spread  over  a  larger  area  (this  area  too  increasing  with  the 
square  of  the  size  of  the  image)  so  that  the  actual  intensity  in  each 
point  of  the  image  is  the  same  as  that  in  the  image  of  your  Elmar. 
Both  lenses  have  the  same  light  transmitting  capacity. 

In  other  words,  the  actual  diameter  of  the  lens  is  no  useable 
measure  for  the  amount  of  light  collected  by  it.  "We  must  compare 
it  with  the  focal  length  of  the  lens  which,  as  you  know,  also  deter- 
mines the  size  of  the  images.  The  ratio :  focal  length  divided  by  the 
effective  diameter  of  the  lens  has  therefore  been  introduced  as  the 
standard  measure  for  the  light  collecting  power  of  the  lens.  The 
increase  in  exposure  when  closing  the  iris  diaphragm  can  always  fae 
found  by  comparing  the  squares  of  these  ratios. 

A  practical  example  will  illustrate  how  you  must  proceed :  The 
lowest  figure  on  the  aperture  scale  of  the  Elmar  lens  is  f  :3.5.  Since 
the  focal  length  of  this  lens  is  50mm,  the  actual  effective  diameter  of 
the  lens  is  50:3.5  (or  14.3mm).  How  much  longer  do  you  have  to 
make  the  exposure  if  you  close  the  iris  diaphragm  to  f  :4.5  ?  Divide 
the  square  of  4.5  (or  20.25)  by  the  square  of  3.5  (or  12.25)  and 
you  will  find  that  with  the  smaller  aperture  you  must  expose  1.67 
times  as  long.  If  in  the  first  case  (Ms  at  f  :3.5)  you  had  to  give  an 
exposure  of  1  second,  you  must  expose  1.67  seconds  with  the  iris  at 
f  .4.5  in  order  to  obtain  a  negative  of  the  same  density. 

But  if  you  have  once  established  the  correct  exposure  for  certain 
light  conditions  and  a  definite  relative  aperture  of  the  lens  (for  in- 



stance  f  :4.5)  you  can  give  this  exposure  to  any  photo,  regardless  of 
the  focal  length  of  the  lens.  The  Hektor  135mm  at  f  :4.5,  the  Elmar 
90mm  at  f  :4.5,  the  Summar  50mm  at  4.5,  the  Elmar  35mm  at  f  :4.5; 
all  these  lenses  at  these  apertures  require  the  same  time  of  exposure. 
Stick  to  this  rule,  even  if  supersensitive  experts  tell  you  that  they 
have  discovered  minute  variations  in  densities  of  negatives  thus  taken. 
The  latitude  of  the  film  will  protect  you. 

Also  remember  that  the  effective  diameter  of  a  lens,  even  when 
the  iris  diaphragm  is  fully  open,  is  not  equivalent  to  the  diameter  of 
the  first  element  in  the  lens  but  to  the  diameter  of  the  cone  of  rays 
in  an  optical  reference  plane  called  entrance  pupil.  The  size  and 
shape  of  the  first  element  depends  entirely  upon  the  plan  of  design 
of  the  lens  and  can  vary  even  if  the  light  transmitting  power  re- 
mains constant. 

Perspective  and  the  Various  Leica  Lenses 

Before  we  discuss  the  merits  of  the  various  objectives  for  the 
Leica  camera,  a  few  words  must  be  added  in  regard  to  the  perspective 
in  a  photograph  because  the  focal  lengths  of  these  lenses  vary  from 
28mm  to  200mm  and  sometimes  you  may  be  in  doubt  whether  you 
should  go  close  and  use  a  short  focus  lens  or  take  a  lens  of  longer 
focal  length  and  go  farther  away  from  the  object  until  you  see  the 
same  relation  between  image  and  frame  size  in  the  field  of  the  view 

We  have  seen  that  the  focal  length  of  the  objective  determines  the  size 
of  the  image  of  any  object  at  different  distances.  It  is  to  our  advantage 
if  we  become  acquainted  with  the  exact  mathematical  relation  between  the 
focal  length,  the  object  distance,  the  size  of  the  object  and  that  of  the  image. 
This  relation  can  be  expressed  by  the  following1  equation : 

JO  __    D  —  f 
I""         f 

the  symbols  finding  their  interpretations  as  follows: 

0  =  size  of  the  object 

1  =  size  of  the  image 

D  =  Distance  of  the  object  from  the  lens 
f    =  focal  length  of  the  lens. 

This  fundamental  equation  should  remain  in  the  memory  of  every  pho- 
tographer because  he  can  derive  great  benefit  from  it.  The  left  side  repre- 
sents the  ratio  of  reduction  in  the  image.  Here  is  how  you  can  apply  it:^ 

Suppose  you  have  obtained  permission  to  photograph  the  animals  in 
the  zoo.  There  is  a  beautiful  lion  which  you  wish  to  photograph.  The  bars 
of  the  cage  are  about  15  feet  from  where  the  lion  generally  reposes.  Which 
objective  should  you  take  along  so  that  you  can  hold  the  camera  between  the 
bars  of  the  cage  and  snap  the  picture  without  wasting  space  on  the  negative 
for  the  empty  cage? 


The  lion  is  6  feet  long  (72  inches)  and  the  longer  side  of  the  negative 
is  1%  inch.  The  ratio  of  reduction  must  be  72  :  1%  or  48  :  1.  The  object 
distance  is  15  feet  (180  inches) .  The  equation  tells  you  that  the  objective 
which  you  should  use  must  have  a  focal  length  of  3.6  inches  or  about  90mm. 

But  we  can  gain  more  valuable  information  from  this  equation.  You 
know  that  objects  which  are  far  away  appear  small  and  those  which  are 
close  appear  large  in  the  picture.  This  accounts  for  the  perspective  in  the 

The  ratio  at  which  the  image  size  decreases  with  increasing  object 
distance  likewise  depends  upon  the  focal  length  of  the  lens  and  can  easily 
be  determined  with  this  equation. 

Suppose  you  want  to  photograph  the  telegraph  poles  along  the  road 
side.  They  are  about  20  feet  high.  The  first  pole  is  about  75  feet  from 
where  you  stand  and  the  distance  between  each  following  pole  is  75  feet. 
At  first  you  take  a  photograph  with  the  90mm  lens.  The  equation  tells  us 
that  the  image  of  the  first  pole  is  24mm  high,  that  of  the  second  pole  is  only 
12mm  high  or  one  half  the  size  of  the  first  one. 

Now  you  change  to  the  Elmar  50mm,  but  you  remain  standing  where 
you  were.  On  this  negative  the  first  pole  appears  as  an  image  of  only  13mm 
and  the  second'  one  is  about  G^mm.  Although  both  images  are  smaller  the 
second  pole  appears  again  at  one-half  the  size  of  the  first  one.  From  this 
experiment  we  learn  that:  lenses  of  different  focal  lengths,  used  for  photo- 
graphing from  the  same  distance  show  identical  perspective  in  the  image 
but  different  ratios  of  reduction.  The  smaller  the  focal  length  the  greater 
the  ratio  of  reduction. 

But  when  you  use  the  50mm  Elmar  you  can  go  closer  to  the  first 
pole  until  its  image  is  again  24mm  high.  You  must  now  approach  it  until 
you  are  only  41.7  feet  away.  But  now  the  image  of  the  second  pole  is  only 
8.6mm  high  or  only  slightly  more  than  l/3rd  of  the  size  of  the  first  one. 
From  this  experiment  we  learn  that:  lenses  of  different  focal  lengths  used 
for  photographing  so  that  the  ratio  of  reduction  of  the  image  of  one  given 
object  remains  the  same,  show  different  perspective.  Lenses  of  shorter  focal 
length  yield  images  with  more  pronounced  perspective. 

If  you  hold  side  by  side  the  two  photographs  of  the  telegraph 
poles  taken  with  the  90mm  Elmar  and  th^  50mm  Elmar  from  differ- 
ent points  of  view  so  that  the  first  pole  in  both  cases  is  equally  long 
in  the  pictures,  you  may  want  to  know  which  of  the  two  has  more 
natural  perspective.  The  general  problem  involved  is  somewhat  com- 
plicated because  various  factors  are  involved.  For  instance,  we  must 
give  consideration  to  the  size  of  the  enlargement  and  the  distance 
from  which  we  look  at  it.  But  in  general  we  may  assume  that  an 
enlargement  of  5  x  7  inches  is  held  about  10  to  12  inches  from  the  eye 
and  as  the  size  of  the  enlargement  increases  we  also  increase  the  dis- 
tance from  which  we  view  it. 

Under  these  conditions  the  most  favorable  focal  length  of  a 
lens  for  the  negative  size  of  the  Leica  camera  is  50mm.  A  lens  of 
this  focal  length  will  yield  images  of  the  most  natural  perspective. 
It  is,  therefore  not  surprising  that  this  is  the  focal  length  of  the 
most  popular  Leica  lenses. 



Only  if  you  want  to  photograph  from  a  rather  close  distance,  as 
in  portrait  photography,  it  is  advisable  to  select  a  lens  of  slightly 
longer  focal  length.  As  we  come  too  close  to  the  subject,  the  size  of 
the  image  increases  so  rapidly  that  there  is  a  tendency  for  the  image 
of  the  closest  features  to  be  unproportionally  larger  than  that  of  the 
farther  features.  Then  you  obtain  pictures  where  the  nose  is  large 
and  the  ears  are  too  small.  Such  portraits  are  not  nattering.  Some 
photographers  are  of  the  erroneous  opinion  that  for  portrait  photog- 
raphy the  miniature  camera  is  altogether  unuseable.  This  assumption 
is  wrong.  In  fact,  the  miniature  camera  can  produce  portraits  with 
a  perspective  which  is  identical  to  that  which  we  find  in  portraits 
taken  with  cameras  of  larger  negative  size.  A  lens  of  about  73  to 
90mm  will  do  the  trick.  The  reader  who  is  sufficiently  interested  in 
this  problem  will  find  a  detailed  investigation  by  the  writer  in  the 
October  1934  issue  of  Photo  Art  Monthly.  If  we  select  an  objective 
of  still  longer  focal  length,  the  portrait  will  even  lack  in  "plasticity" 
and  the  faces  will  appear  too  flat. 

We  have  gradually  acquired  knowledge  about  some  of  the  most 
fundamental  principles  of  photographic  lenses  in  general  and  can 
appreciate  the  special  requirements  of  lenses  suitable  for  miniature 

Fig.  45     Indian  Guides 

Elmar  90mm  Lens,   Panatomic  Film 

Felix  Schoedsack 

cameras.    The  family  of  Leica  lenses  has  grown  steadily  and  we  may 
summarize  our  knowledge  by  discussing  each  of  them. 

The  Hektor  28mm  f:6.3.  This  lens  has  the  shortest  focal  length  of 
all  available  for  the  Leica  camera;  as  such  it  yields  pictures  having  the 
greatest  depth  of  focus.  Even  with  its  diaphragm  wide  open  at  f  :6.3  when 
fixed  at  infinity  the  range  of  sharpness  of  this  lens  will  include  everything 
from  infinity  to  within  as  little  as  12  feet  from  the  camera.  Incidentally, 
the  short  focal  length  of  this  lens  accounts  for  the  great  reduction  in  size 
of  the  image  of  objects  that  are  apparently  near  the  camera.  This  .power 
of  reduction  permits  us  to  cover  a  much  larger  field  and  to  crowd  more 
things  into  a  single  frame  of  the  Leica  negative.  The  lens  actually  collects 
rays  within  an  angle  of  76°  into  the  frame  of  the  negative.  It  is  distinctly 
a  wide  angle  lens.  The  perspective  which  is  quite  accentuated  off ers  attrac- 
tive possibilities  to  the  skillful  photographer  especially  on  account  of  its 
almost  unlimited  depth  of  focus.  These  two  factors:  rapidly  receding  per- 
spective and  depth  of  focus  are  very  useful  in  the  treatment  of  architectural 
subjects.  The  "super  speed"  photographer  may  consider  this  lens  slow 
because  its  largest  opening  is  only  f  :6.3.  One  should  realize,  however, 
that  for  a  specifically  wide  angle  lens  having  such  extremely  short  focal 
length,  yielding  images  so  completely  free  from  distortion — the  aperture 
of  f  :6.3  may  be  considered  an  achievement  of  'optical  craftsmanship.  The 
lens  comes  in  a  non-collapsible  mount,  its  short  focal  length  making  it 
possible.  A  special  view  finder  which  renders  a  clear  and  brilliant  image 
of  the  field  is  available  for  this  lens. 

The     Hektor     28mm     Wide-Angle 

Lens    with    its     Special    Brilliant 

View  Finder. 

The  Elmar  35mm  f:3.5.  This  is  another  member  of  the  wide  angle 
lens  family  which  covers  an  angle  of  view  of  65°.  While  the  angle  of 
vision  is  somewhat  smaller  than  that  of  the  Hektor  28mm,  this  is  amply 
compensated  by  greater  light  collecting  power  of  its  comparatively  large 
aperture  of  f  :3.5.  Pictures  made  with  this  lens  have  considerable  depth 
of  focus  and  their  perspective  is  more  nearly  approaching  that  of  normal 
vision.  These  two  features  of  the  Elmar  35mm  lens  make  it  an  ideal 
medium  for  snapshooting.  Set  for  infinity,  with  its  diaphragm  slightly 
stopped  down  it  requires  almost  no  focusing.  From  the  depth  of  focus 
scale  we  know  that  with  the  diaphragm  set  for  f :6.3,  when  the  lens  is 
focused  for  30  feet,  the  range  of  sharpness  will  extend  from  10  feet  to 
infinity.  Thus  focused,  the  camera  can  be  kept  in  constant  readiness  in 
the  pocket  or  in  the  Everready  case.  Due  to  its  short  focal  length  the  lens 
does  not  need  a  collapsible  mount  and  protrudes  only  slightly  beyond  the 
body  of  the  camera,  rendering  it  very  handy  for  quick  work.  Though 
its  field  of  view  is  adequately  covered  by  the  Vidom  Universal  View  Finder 
so  many  people  find  it  more  convenient  and  expedient  to  use  in  connection 
with  this  lens  the  special  small  view  finder  available  for  it.  It  fits  snugly 
into  the  clip  of  the  camera  upon  the  range  finder,  combining  maximum 
convenience  with  minimum  of  bulk.  For  general  outdoor  photography  the 



speed  of  f:6.3  is  quite  adequate.  If  candid  photographs  have  to  be  made 
in  artificial  light,  when  critical  focusing-  may  require  more  time  than  is 
available — the  lens  can  be  left  wide  open  and  set  to  an  approximate  focus. 
The  aperture  of  f  :3.5  is  often  sufficient  to  secure  usable  negatives  even  in 
artificial  illumination  if  super-sensitive  film  is  used. 

Fig.  46  Elmar  35mm 
f:3.5  Lens  with  its 
Special  View  Finder 
which  fits  into  the 
camera  clip. 

The  50  mm  Lenses 

The  Elmar  50mm  f  :3.5.  This  is  the  lens  which  made  the  Leica  camera 
famous.  The  sharpness  of  the  pictures  taken  with  this  lens  was  responsible 
for  the  immense  success  of  the  Leica.  It  may  be  remembered  that  more 
than  35,000  Leica  cameras  were  sold  before  a  model  with  interchangeable 
lenses  was  offered.  The  Elmar  50mm  is  still  the  best  standard  lens  upon 
which  you  can  build'  your  equipment.  This  lens  really  set  a  new  standard  for 
the  correction  of  the  optical  equipment  of  cameras  and  carries  a  great  share 
of  the  credit  for  having  put  across  the  idea  of  miniature  photography.  The 
Elmar  plan  of  design  was  later  on  used  for  four  other  Leica  lenses  of  35mm, 
90mm  and  105  mm. 

The  maximum  sharpness  in  the  negative  prevails  when  the  objective 
is  stopped  down  to  about  f:6.3  or  f:9;  and  upon  closing  the  iris  further 
there  is  no  noticeable  decrease  of  sharpness  in  the  negative. 

The  depth  of  focus  of  this  Elmar  50mm  is  still  remarkable  and  it  was 
with  this  lens  that  the  surprising  possibilities  of  miniature  cameras  in 
combining  speed  of  the  lens,  depth  of  focus  and  sharpness  of  the  negative 
were  first  demonstrated  so  successfully  to  the  public  who  became  at  once 
enthused  about  miniature  photography.  The  perspective  of  its  pictures  is 
natural.  The  lens  can  even  be  used  for  portrait  photography  although  in 
cases  where  extreme  close-ups  are  taken,  it  should  not  be  used,  unless  you 
make  use  of  a  simple  trick.  Place  the  subject  somewhat  farther  away  and 
when  you  make  the  enlargement,  use  only  2/3rds  of  the  center  portion  of 
the  negative. 

Fig.  47    Elmar 
50mm  f  :3.5   Lens 

Fig.  48  Hektor 
50mm  f:2.5  Lens 


In  summarizing  the  merits  of  this  Elmar  5iOmm  one  point  should  not 
be  forgotten:  the  price  question.  Before  the  Leica  appeared,  an  objective 
of  an  aperture  of  f  :4.5  for  a  large  camera  was  considered  extremely  fast, 
because  faster  lenses  were  hardly  obtainable.  Faster  lenses  were  not  made 
because  their  price  would  have  been  so  prohibitive,  that  there  would  not  have 
been  any  market  for  them.  Only  when  the  Leica  with  its  objectives  of 
short  focal  length  made  its  debut,  faster  lenses  became  accessible  for  the 

The  Hektor  50mm  f:2.5 

This  lens  differs  from  the  Elmar  of  the  same  focal  length  in  two 
respects:  in  the  first  place,  the  name  implies  that  it  is  built  upon  a  different 
plan  of  design  and  secondly  it  has  a  higher  speed.  It  was  the  thirst  of 
the  amateur  for  still  more  speed  which  was  to  be  satisfied  with  this  new 
type  lens  and  this  higher  speed  necessitated  a  new  plan  of  construction. 
The  difficulty  before  the  lens  designer  was  great  indeed.  The  cry  for  more 
speed  did  not  indicate  whether  the  amateur  knew  how  much  more  expensive 
a  good  lens  of  this  type  would  have  to  be.  The  step  from  f  :3.5  to  f  :2.5 
means  an  increase  of  speed  of  100%.  You  may  know  that  if  the  top  speed 
of  a  car  would  have  to  be  doubled,  it  would  become  necessary  to  design  a 
new  model  which  may  be  three  to  four  times  as  expensive.  Such  margin 
was  not  available  for  the  lens  designer.  The  speed  increase  would  have  to 
be  gained  by  making  a  sacrifice  in  some  other  respect.  If  we  follow  the 
historical  course  of  events  we  must  not  forget  that  when  the  Hektor  50mm 
was  created  an  enlargement  of  5  x  7  inches  was  considered  rather  a  satis- 
factory size.  Strange,  how  quickly  fashions  change!  From  the  short  skirt 
to  the  long  skirt  was  hardly  more  than  a  year.  From  the  5x7  enlargement 
to  the  monstrous  size  of  16  x  20  from  a  Leica  negative  was  only  a  few 
years ! 

But  the  Hektor  50mm  with  100%  increase  in  speed  and  a  slight  de- 
crease in  sharpness  at  full  aperture,  was  so  designed  that  even  if  the  iris 
was  closed  only  to  f  :4.5  or  f  :6.3  the  sharpness  equalled  if  not  surpassed 
that  of  the  pictures  of  the  Elmar  50mm.  And  furthermore,  this  lens  has 
one  other  slight  advantage  over  the  Elmar.  Its  plan  of  design  made  a 
slightly  higher  color  correction  possible.  Critical  and  impartial  amateurs 
may  have  noticed  slightly  superior  results  with  the  Hektor  50mm  over  those 
of  an  Elmar  50mm  when  using  panchromatic  films. 

In  spite  of  these  advantages  and  a  moderate  price  the  Hektor  50mm 
lost  some  of  its  popularity  as  soon  as  a  faster  lens  became  available, 
although  at  a  still  higher  price. 

The  Summar  50  mm  F:2 

This  lens  must  be  considered  as  a  triumph  of  the  science  of  optics. 
You  will  remember  that  the  quality  of  a  lens  can  be  judged  by  finding 
how  much  the  iris  diaphragm  can  be  opened  with  beneficial  increase 
in  sharpness  of  the  picture.  When  we  come  to  as  high  an  aperture 
as  f  :2  we  may  be  satisfiedby  seeing  how  little  the  sharpness  decreases. 
The  Summar  50mm  at  this  high  aperture  yields  images  so  sharp  that 
even  when  enlarged  to  the  size  of  8  x  10  inches  the  smallest  detail  is 
still  beyond  the  limit  of  resolving  power  of  the  human  eye  if  the  photo 
is  held  10  inches  from  the  eye. 



With  the  iris  diaphragm  fully  open  the  speed  of  the  Summar 
50mm  is  three  times  as  high  as  that  of  the  Elmar  at  its  best.  This 
speed  is  enough  to  enable  the  photographer  to  take  photos  even  under 
extremely  unfavorable  light  conditions.  Thus  it  was  with  this  fast 
lens  that  the  Leiea  camera  conquered  another  field :  candid  and  stage 
photography.  And  as  the  miniature  camera  is  used  for  more  and  more 
seemingly  impossible  tasks,  these  fast  lenses  also  opened  the  field  of 
snapshooting  with  infra-red  sensitive  films  and  filters.  These  invisible 
rays  to  which  film  emulsions  can  be  made  sensitive,  are  so  different 
from  the  rest,  that  it  is  not  surprising  that  they  refuse  to  unite  with 
the  visible  rays  in  forming  an  image,  even  if  they  pass  through  as 
excellently  corrected  a  lens  system  as  the  Summar  50mm. 

But  the  focusing  scale  of  the  Summar  provides  for  a  correction 
so  that  if  you  have  eliminated  the  other  rays  by  means  of  a  filter, 
you  can  still  obtain  sharp  pictures  with  infra-red  rays.  On  this  scale 
you  will  find  two  index  marks,  one  of  which  is  provided  with  a  letter 
R.  Suppose  you  have  focused  the  camera  on  an  object  and  the 
regular  index  mark  points  to  30  feet.  Before  you  take  the  photo, 
simply  turn  the  focusing  mount  slightly  until  the  mark  with  the 
letter  E  points  to  the  distance  of  30  feet.  Then  you  will  obtain  a 
sharp  picture. 

Fig.  49  Summar  50mm 
f:2  Lens  in  Collapsible 

The  Xenon  50mm  f  :1.5 
Superspeed  Lens. 

The  Xenon  50mm,  f:1.5.  As  this  edition  goes  to  press  we 
learn  of  the  fulfillment  of  the  dream  of  so  many  Leica  fans.  A 
lens  of  the  ultra  sp-eed  of  f  :1.5  of  the  standard  focal  length  of 
50mm  has  become  available.  This  addition  to  the  family  of  the 
Leica  lenses  is  so  recent  that  only  this  last  minute  announcement 
of  it  can  be  made  in  this  edition.  First  photographs  made  with 
this  lens  reveal  a  remarkable  over-all  sharpness  throughout  the 


entire  negative  area  up  to  the  very-  edge  and  corner  of  it.  This  is 
an  outstanding  accomplishment  for  a  lens  of  such  high  light  trans- 
mitting power.  Two  such  photographs  made  under  ordinary  light 
conditions  with  the  lens  wide  open  are  being  offered  to  prove  the 
claim.  The  lens  is  finished  in  beautiful  and  durable  chromium  and 
its  mount  is  so  designed  that  its  rotation  for  critical  focusing  can 
be  accomplished  either  by  moving  the  regular  locking  thumb-knob 
or  by  grasping  the  outer  knurled  collar  of  its  mount.  Some  people 
find  that  the  latter  method  assures  smoother  operation.  This  lens 
should  gratify  the  yearning  for  high-speed  lenses  of  even  the  most 
radical  speed  fiends  for  some  time  to  come. 

Eddie  Cantor     by  J.  Winton  Lemen    Oakland  Bridge  Anton  F.  Baumann 

Xenon   50mm,    f:1.5,    1/100    sec.  Hektor   28mm,    f:12.5,    1/40,    Panatomic, 

the  Hektor  73  mm  F:1.9 

This  lens  has  a  slightly  noticeable  softness  at  full  aperture.  But 
this  trace  of  lack  of  sharpness  is  very  much  less  pronounced  than 
that  in  its  cousin  of  50mm  focal  length.  Such  improvement  could  be 
accomplished  because  in  the  plan  of  design  of  the  73mm  lens  it  was 
preferred  to  place  perfection  of  correction  before  the  necessity  of 
a  low  price. 



The  lens  is  perhaps  the  best  among-  those  offered  for  the  Leica 
for  the  purpose  of  portrait  photography  and  here  this  minute  effect 
of  softness  is  rather  a  benefit.  In  portrait  photography  the  smaller 
range  of  depth  of  focus  which  results  from  the  longer  focal  lengtli 
and  higher  speed  is  also  an  advantage  because  the  subject  of  interest 
can  thus  stand  out  more  distinctly  against  the  blurred  background. 

With  the  diaphragm  closed  to  f  :4.5  or  more,  the  sharpness  of  the 
pictures  obtained  with  the  Hektor  73mm  also  surpasses  that  of  the 
pictures  taken  with  the  Elmar  50mm,  especially  when  panchromatic 
film  is  used. 

Fig.  50     Hektor  73mm  f  :1.9  Lens  Fig.  51     Elmar  90mm  f  :4  Lens 

The  Elmar  90  mm  F:4 

The  general  characteristics  of  this  lens  need  hardly  be  enumer 
ated  because  they  are  evident  from  the  preceding  general' remarks.  In 
regard  to  sharpness  it  fulfills  every  expectation.  The  depth  of  f oeus 
is  naturally  smaller  than  that  of  the  Elmar  50mm.  But  in  outdoor 
photography  the  lens  will  mostly  be  used  for  longer  distances  and 
then  the  depth  of  focus  is  sufficient  for  all  purposes.  Its  speed  is 
high  considering  the  rather  long  focal  length.  It  is  also  an  ideal 
objective  for  portrait  work. 

Due  to  its  price,  which  is  lower  than  that  of  the  Hektor  73mm, 
the  Elmar  90mm  may  also  deserve  preferred  consideration  in  com- 
pleting a  lens  equipment.  'With  three  lenses,  of  35mm,  50mm,  and 
90mm  focal  length,  almost  any  task  can  be  fulfilled. 

The  Thambor  90mm  f:2.2 

Undoubtedly  this  lens  will  contribute  considerably  towards  a  successful 
invasion  of  the  field  of  Portrait  Photography  with  the  Leica  camera  and 
will  convince  those  who  still  have  serious  objections  to  portrait  photo graphy 
wi£h  this  small  camera.  Its  focal  length  is  ideal  for  portrait  photography 
and  its  extremely  high  speed  offers  three  distinct  advantages.  In  the  first 


place,  it  permits  a  reduction  of  the  depth  of  focus  which  is  often  necessary 
in  portrait  photography  when  we  wish  to  have  the  subject  stand  out  against 
a  soft  or  unsharp  background.  Secondly,  this  high  speed  of  the  lens  permits 
shorter  exposures  or  less  light,  so  that  even  under  unfavorable  light  condi- 
tions it  may  be  possible  to  take  snapshots.  This  is  an  important  point  if  we 
aim  for  natural  and  unposed  expressions  of  the  subject  and  wish  to  avoid 
the  somewhat  self-conscious  and  lifeless  artificial  effects  which  are  so  often 
found  in  posed  portraits. 

Finally,  the  high  relative  aperture  and  the  very  peculiar  and  entirely 
novel  plan  of  design  of  this  lens  make  it  possible  to  obtain  a  soft1  focus 
effect  which  can  be  varied  within  wide  limits.  The  means  which  are  avail- 
able for  this  purpose  are  somewhat  unusual  and  quite  ingenious.  Since 
aside  from  the  well  known  means  of  increasing  the  sharpness  of  soft 
focus  lenses  by  closing  the  iris  diaphragm  (thus  reducing  the  amount  of 
spherical  aberration  which  the  marginal  rays  cause,  and  which  produce 
the  soft  focus  effect)  there  is  also  the  possibility  of  eliminating  the  rays 
in  the  center  by  introducing  a  so-called  "center  spot". 

This  "Center  Spot"  is  introduced  over  the 
front  of  the  lens  by  means  of  a  disc  of  opti- 
cally flat  thin  glass  in  a  screw-in  mount  which 
has  a  small  semi-opaque  spot  in  its  center, 
which  "closes"  the  center  of  the  lens  to  all 
light.  This  method  of  obtaining  a  soft  focus 
creates  very  pleasing  effects  in  portrait  pho- 
tography as  well  as  general  photography  with 
back  light. 

When  this  lens  is  "stopped  down"  further, 
the  image  will  be  really  crisp  and  sharp  so  that 
the  Thambar  can  also  be  used  for  regular  land- 
scape photography  and  other  purposes.  These 

TTV     co    mi     mi       u      ™  f eatures  and  the  agreeable  fact  that  the  Tham- 

Fig.  52    The  Thambar  90mm  ,  .  , .     ,      ,  .     ,    ,         . ,     . 

f:2.2  Lens  with  its  "Center  bar  1S   relatively  low   priced    (considering  its 

Spot"   Disc   in   a   Screw-in  very  high  relative  aperture)  make  it  a  useful 

Mount  and  versatile  Leica  lens. 

The  Elmar  105  mm  F:6.3 

In  many  ways  similar  to  the  90mm  lens,  this  Elmar  may  be  pre- 
ferred by  the  tourist  who  wishes  to  economize  in  weight  of  equipment 
and  needs  the  longer  focal  length  for  photography  at  long  distance. 
The  lower  speed  is  not  directly  objectionable  because  when  you  take 
a  picture  from  the  peak  of  a  mountain  to  the  next  you  usually  have 
ample  light  at  your  disposal.  (As  this  edition  goes  to  press  we  learn 
that  the  production  of  this  lens  is  being  discontinued.) 



The  Hektor  135mm  f:4.5 

This  is  decidedly  a  lens  for  long  distance  photography.  Although 
still  useable  for  portrait  work,  the  critical  judge  may  notice  a  certain 
flatness  (lack  of  third  dimension)  in  portraits  taken  with  the  Hektor 

These  lenses  of  long  focal  length  are  sometimes  called  Teleob- 
jectives.  The  expression  is  misleading,  to  say  the  least.  The  term 
actually  refers  to  a  type  of  long  focus  objectives  with  a  very  definite 
plan  of  design,  consisting  of  a  combination  of  a  convex  lens  system. 
As  you  will  remember,  the  Hektor  type  has  improved  color  correc- 
tion and  at  apertures  not  exceeding  f  :4.5  it  yields  images  of  per- 
fect sharpness.  Those  who  use  panchromatic  or  infra-red  sensitive 
film  with  red  or  infra-red  filters  may  find  the  Hektor  135mm  the 
best  lens  for  long  distance  photography. 

Fig.  53     Hektor  135mm  f  :4.5  Lens 

The  Telyt  200mm  (8  in.)  f:4.5 

This  new  lens  is  a  Tele-Objective  in  the  full  sense  of  the  term 
(a  true  TELEPHOTO  lens).  It  is  so  designed  that  the  distance 
between  the  film  plane  and  the  lens  is  shorter  than  the  focal  length, 
a  feature  which  is  characteristic  of  the  Tele  System  on  which  this 
lens  is  based.  This  is  obtained  by  introducing  a  negative  lens  element 
back  of  the  positive  lens  element.  Thus,  while  the  focal  length  of 
the  Telyt  is  65mm  longer  than  that  of  the  135mm  lens  its  barrel  is 
only  3.3mm  longer.  It  will  be  remembered  that  the  Hektor  135mm 
lens  is  not  built  on  the  principle  of  the  Tele  System  but  is  a  regular 
anastigmat  of  long  focus.  The  Telyt  is  the  first  Tele  System  objec- 
tive in  the  series  of  Leica  lenses.  Its  correction  is  excellent  so  that 
it  produces  images  entirely  free  from  distortion.  Particular  atten- 
tion'was  given  to  chromatic  correction  which  makes  the  lens  available 
for  long  distance  photography  with  panchromatic  and  Infra-Red 
film  in  connection  with  red  and  Infra-E-ed  filters.  Excellent  results 
may  be  expected  in  this  type  of  work.  It  should  be  remembered, 
however,  that  for  long  distance  photography  clear  atmospheric  con- 
ditions are  quite  essential.  While  aerial  haze  can  be  overcome  with 


the  aid  of  haze-cutting  filters,  it  is  almost  hopeless  to  attempt  to 
photograph  across  so-called  ''heat-waves"  or  heat  currents  caused 
by  rapidly  rising  layers  of  air  heated  by  sunrays  or  by  heat  reflected 
from  the  ground.  Such  conditions  cause  local  variations  of  the 
refracting  power  of  the  air,  resulting  not  only  in  decreased  sharpness 
of  the  photographic  image  but  frequently  in  its  complete  distortion. 

The  long  focal  length  of  this  lens  made  it  possible  (and  neces- 
sary) to  equip  it  with  a  special  mirror  reflex  focusing  device  con- 
tained in  a  small  and  compact  dice-like  box  which  is  attached  directly 
to  the  camera.  For  this  particular  lens  such  a  method  of  focusing 
was  preferred  to  the  direct  coupling  to  .the  automatic  range-finder. 
It  combines  the  advantages  of  extremely  accurate  focusing  with  the 
convenience  of  viewing  the  entire  picture  on  the  ground  glass  of  the 
mirror  reflex  box  through  a  5x  or  a  30x  magnifier. 

Best  results  can  be  obtained  with  the  Telyt  only  if  a  good  tripod 
is  used  or  if  the  camera  and  lens  are  otherwise  rigidly  supported. 

The  Telyt,  as  compared  with  the  standard  50mm  lens,  yields 
a  magnification  of  4x.  Its  view  angle  is  approximately  12°.  Its 
focusing  mount  permits  direct  focusing  by  scale  from  infinity  to 

Fig.  54  New  Telyt  200mm  f :  4.5 
Telephoto  Lens.  Shown  Com- 
plete With  Reflex  Housing  5x 
Magnifier  and  Synchronized  Re- 



Two  Photographs  Taken 
From  the  Same  Position 
with  the  28mm  Wide 
Angle  and  the  Telyt  Lenses 

Fig.  55  Photograph  Made 
with  the  200mm  Telyt 

Fig.  56     General  Wide  Angle  View  Obtained  with  the  Hektor  28mm  Lens 


9  feet.  At  9  feet  it  covers  an  area  of  approximately  12  x  18  inches. 
Special  extension  tubes  are  available  for  this  lens  permitting  close- 
ups  down  to  a  working  distance  of  4  feet  from  the  camera,  at  which 
distance  the  lens  will  cover  an  area  of  4  x  6  inches,  yielding  a 
magnification  on  the  negative  of  approximately  4^x. 

The  basic  principle  of  interchangeability  of  Leica  lenses  has 
been  maintained  in  the  Telyt.  The  mirror  reflex  housing  can  also 
be  used  with  other  Leica  lenses,  particularly  with  the  Hektor  135mm, 
which  can  be  supplied  in  a  special  shortened  mount  (without  the 
automatic  coupling),  which  is  simply  screwed  into  the  reflex  housing 
in  place  of  the  Telyt.  When  thus  used  the  lens  is  acting  as  a  normal 
135mm  objective  and  can  be  used  up  to  infinity. 

Using  the  Mirror  Reflex  with  Other  Leica  Lenses 

Other  Leica  lenses  of  shorter  focal  lengths  are  limited  to  close- 
ups  when  used  in  connection  with  the  reflex  housing.  If  the  focusing 
mount  of  the  respective  lenses  is  set  for  infinity  the  resulting  ratio 
of  reduction  or  magnification  respectively  (on  the  film)  is  as  follows: 

Lens:  Focal  Length         Ratio  of  reduction  (on  film) 

(lens  set  for  infinity) 

Hektor    135mm 1:2.2 

Elmar    105mm 1:1.7 


Thambar   > 90mm 1:1J5 

Hektor    73mm 1:1.2 

Ratio  of  magnification  (on  film) 

(lens  set  for  infinity) 

50mm 1.2:1 



Elmar    35mm 1.8:1 

Hektor    28mm 2.2:1 

For  estimating  correct  exposure  with  these  lenses,  whose  focal  lengths 
are  reduced  by  their  use  in  connection  with  the  reflex  housing,  formulas 
offered  in  the  chapter  on  copying  and  close-up  photography  should  be  con- 
sulted. The  length,  of  the  reflex  housing  (considered  as  an  extension 
tube)  is  62mm. 
Front  Lenses  and  Close  Distance  Photography 

The  problem,  of  photographing  objects  at  close  range  can  be 
solved  in  two  different  ways:  either  we  can  introduce  intermediate 
extension  tubes  to  increase  the  distance  from  the  lens  to  the  plane  of 
the  negative,  or  we  can  reduce  the  focal  length  of  the  lens  system  by 
placing  front  lenses  before  the  regular  objective. 

The  use  of  extension  tubes  directly  on  the  camera  together  with  table  of  working 
distances,  ratio  of  magnification  etc.  will  be  found  on  page  195. 



As  we  see  from  the  Front  Lens  tables,  these  auxiliary  optical 
systems  permit  the  photographing  of  objects  with  the  Leica  camera 
from  31/2  feet  to  10  11/16  inches  from  the  camera  back.  The  smallest 
object  which  can  thus  be  photographed  to  fill  the  negative  frame 
measures  3%x5  inches.  If  we  wish  to  compare  the  optical  principle 
of  photography  with  Front  Lenses  and  with  intermediate  rings,  we 
must  again  recall  a  few  optical  principles.  It  will  be  evident  that 
if  in  figure  58  the  object  point  would  have  been  infinitely  far  away, 
a  practically  parallel  bundle  of  rays  would  have  entered  the  lens. 
We  have  neglected  so  far  to  mention  that  if  the  lens  is  so  designed 
that  it  will  converge  with  the  highest  perfection  any  parallel  bundle 
of  rays,  it  is  by  no  means  to  be  understood  that  this  same  lens  system 
will  converge  with  the  same  perfection  (although  in  another  plane) 
a  divergent  bundle  of  rays  from  an  object  point  which  is  nearer  to 
the  lens.  In  other  words,  a  lens  which  will  yield  the  sharpest  image 
without  spherical  aberration  when  the  object  is  far  away  will  not 
yield  as  crisp  an  image  when  the  object  is  close  to  the  lens.  As  the 
object  moves  from  infinity  to  minimum  distance  of  3^  ^eet  the 
amount  of  divergence  of  the  bundles  of  rays  entering  the  lens  is  quite 
negligible,  but  if  the  object  comes  considerably  closer  the  spherical 
aberration  would  become  so  noticeable  that  the  images  would  suffer 
considerably  in  quality. 

If  we  add  a  Front  Lens  to  the  Leica  objective,  we  reduce  the 
focal  length  of  the  entire  lens  system  in  a  peculiar  way  and  we  learn 
from  the  tables  that  for  instance  through  the  addition  of  Front  Lens 
No.  1  to  the  Elmar  50mm  we  can  set  the  focusing  mount  to  infinity 
when  the  object  is  only  39%  inches  away.  The  Front  Lens  converts 
the  slightly  divergent  rays  into  a  parallel  bundle  so  that  through 
this  addition  the  Elmar,  in  order  to  photograph  an  object  at  39^ 
inches,  yields  an  image  of  the  same  quality  as  one  photographed  at 
infinity  without  the  Front  Lens.  This  same  principle  is  consistently 
applied  so  that  with  the  Leica  focused  to  31/2  feet,  we  can  photograph 
objects  at  an  actual  distance  of  22  9/16  inches  when  we  add  Front 
Lens  No.  1.  The  front  lens  tables  give  further  details. 

What  we  have  to  cope  with  particularly  when  photographing  at  short 
distance  is  the  misbehavior  of  light  which  is  called  "spherical  aberration". 
We  will  recall  that  the  marginal  rays  have  a  tendency  to  converge  closer 
to  the  lens  than  the  rays  passing  through  the  center  of  the  objective.  The 
marginal  rays  can  always  be  eliminated  by  closing  the  iris  diaphragm. 
Since  in  close-up  photography,  every  optimum  of  detail  rendition  is  abso- 
lutely essential,  we  cannot  afford  to  leave  the  diaphragm  wide  open  but 
have  to  close  it  to  such  an  extent  that  through  compromise  of  the  small 
remaining  defects  in  a  lens  system  which  have  been  described  before,  the 


actual  sharpness  of  the  image  is  most  favorable.  The  front  lens  tables  con- 
tain definite  information  how  much  the  Leica  lenses  have  to  be  stopped  down 
for  the  Front  Lenses  and  various  distances. 

Supplementary  Front  Lens        Elmar  lens 
Fig-.  58     Path  of  Rays  in  the  Elmar  Lens  with  Supplementary  Front  Lens 

Another  interesting  fact  relates  to  the  f  values  of  the  regular  Leica 
lenses.  As  long  as  we  use  Front  Lenses  for  close-up  photography,  original 
f  values  retain  their  value  because  the  actual  light  intensity  gathered  by 
the  objective  and  expressed  by  the  so-called  f  value  is  represented  by 
the  figure:  distance  from  lens  to  image  divided  by  the  diameter  of  the 
lens.  Since  the  use  of  a  front  lens  enables  us  to  use  the  same  focusing 
mount  at  close  distance  we  find  that  for  photography  of  an  object  at  39% 
inches  with  front  lens  No.  1  the  distance  from  the  lens  to  the  film  is  the 
same  as  if  we  would  photograph  an  object  at  infinity  without  the  front 
lens.  It  is  therefore  possible  to  measure  the  actual  intensity  of  the  object 
with  a  standard  exposure  meter  and  compute  the  value  for  the  respective 
aperture  of  the  lens  at  which  we  take  the  photograph. 

These  hints  may  be  valuable  for  those  who  use  the  Front  Lenses 
and  it  may  be  added  that  these  auxiliary  optical  devices'  are  par- 
ticularly advantageous  if  we  wish  to  obtain  the  crispest  sharpness 
and  best  detail  rendition  in  flat  objects  within  the  range  of  distances 
indicated  in  the  Front  Lens  tables.  The  question  of  photography 
at  still  closer  distances  is  covered  in  Chapters  9,  17,  18,  20,  and  21. 

Proper  Care  of  Lenses 

It  seems  advisable  to  conclude  with  some  suggestions  relative  to 
the  care  of  the  miniature  camera  lenses.  All  lenses  are  made  with  an 
accuracy  which  can  hardly  be  found  in  any  other  piece  of  manu- 
factured goods.  The  lens  surfaces  must  be  so  smooth  and  so  accu- 
rately spherical  that  even  a  deviation  of  l/100,000th  of  an  inch 
would  affect  their  performance.  It  is  quite  evident  that  such  a  delicate 
and  accurate  piece  of  equipment  requires  special  care  and  can  easily 
be  ruined  by  careless  handling. 

The  first  rule  for  the  care  of  lenses  is  therefore:  keep  the  lens 
surfaces  free  from  dust  and  other  impurities.  When  the  lens  is  at- 
tached to  the  camera  and  not  in  use,  see  to  it  that  it  is  covered  with 
the  lens  cap.  When  the  objective  is  removed  from  the  camera,  use 
the  dust  cap  to  close  the  other  side  so  that  the  lens  surfaces  are  not 
exposed  and  no  dust  can  collect  on  them. 



Should  the  surfaces  show  deposits  of  dust  or  other  impurities, 
do  not  try  to  remove  it  by  rubbing  the  surface  with  your  fingers. 
You  may  wipe  the  surfaces  with  a  piece  of  silk  cloth  or  with  a  piece 
of  lens  paper.  You  can  also  use  a  fine  camel-hair  brush.  In  any 
case  it  is  imperative  that  the  surface  be  wiped  very  gently.  The 
dust  in  the  air  is  full  of  little  abrasive  particles  which  could  scratch- 
the  surface  of  the  lens.  The  smallest  scratch  is  in  comparison  to 
the  length  of  a  light  wave  like  a  deep  and  wide  trench  since  a  light 
wave  is  as  small  as  l/50,000th  inch.  You  may  secure  a  small  bottle 
of  xylol  and  a  package  of  lens  paper  and  always  moisten  the  paper 
in  the  xylol  when  cleaning  the  lens  surfaces.  In  wiping  the  lens, 
have  the  paper  make  a  circular  motion. 

If  a  lens  surface  is  once  scratched,  it  is  not  possible  to  simply 
repolish  this  surface  beca,use  such  action  would  make  the  entire  lens 
thinner  and  would  affect  the  optical  performance.  Only  a  replace- 
ment of  this  lens  can  fully  repair  the  damage. 

Under  no  circumstances  should  the  photographer  try  to  take  the 
lens  apart.  Such  warning  may  seem  unnecessary  to  many  miniature 
camera  owners,  yet  it  is  given  in  view  of  experiences  which  have 
repeated  themselves  only  too  frequently.  A  photographer  may  try  to 
insert  a  color  filter  between  the  lens  elements,  may  try  to  clean  the 
inside  surface  or  find  another  excuse  for  satisfying  his  curiosity  and 
take  the  lens  apart.  He  will  be  sadly  disappointed  when  he  finds  out 
how  hard  it  is  to  reassemble  the  lens  so  that  no  dust  remains  inside. 
The  lenses  are  assembled  by  the  manufacturer  in  rooms  which  are 
absolutely  free  from  dust  and  special  instruments  are  used  to  keep 
dust  from  the  insides  of  the  lens. 

Sometimes  lenses  show  a  few  very  minute  bubbles  in  the  glass. 
These  are  not  objectionable.  The  area  of  one  bubble  in  comparison 
to  that  of  the  entire  lens  surface,  is  very  small  and  whatever  small 
amount  of  light  is  thrown  off  its  course  by  this  bubble  is  by  far  too 
minute  to  cause  any  photographically  recordable  light  impression.  A 
long  scratch  over  the  lens  surface  is  much  more  serious. 

Altogether  the  photographer  in  trying  to  repair  a  lens  should  re- 
strict his  activity  to  a  minimum.  As  long  as  the  objective  is  kept 
closed  by  lens  and  dust  cap  no  danger  of  serious  trouble  will  ever 
arise.  If  something  irregular  comes  into  evidence,  the  objective 
should  rather  be  sent  to  the  manufacturer. 


Sahuaro  James  M.  Leonard 

Elmar  35mm,  l/100th  second  at  f  :12.5,  No.  1  Filter,  Du  Pont  Superior  Film 




A  filter  is  a  medium  which,  allows  light  rays  of  a  certain  kind  to 
pass  through,  while  it  is  more  or  less  impervious  to  others.  From  its 
very  definition,  it  appears  that  its  function  is  purely  subtractive ;  it 
adds  nothing  in  the  way  of  illumination ;  it  merely  eliminates  from 
light  certain  qualities  which  may  be  undesirable.  This  is  the  reason 
for  the  increase  of  exposure  generally  required  when  filters  are  used. 
Thus  a  filter  should  be  looked  upon  as  just  another  means  of  con- 
trolling light  and  illumination  in  addition  to  the  others  at  our  dis- 
posal. These  are  the  shutter — for  control  of  length  of  time  during 
which  the  light  is  permitted  to  reach  the  film;  the  lens  diaphragm — 
for  control  of  quantity  and  optical  quality;  the  filter — for  control  of 
color  quality  or  intensity.  Additional  means  of  light  control  are 
available  in  the  form  of  reflectors  and  diffusers. 

Photographic  color  filters  are  usually  made  of  glass.  The  coloring 
which  renders  it  capable  of  absorbing  certain  colors  of  light,  while 
allowing  others  to  pass  freely,  is  imparted  to  it  by  several  methods. 
Certain  dyes  are  mixed  with  the  glass  in  its  molten  state,  thus  render- 
ing it  colored  before  polishing  and  shaping.  This  provides  the  most 
satisfactory  type  of  filter  for  use  directly  on  the  camera  lens,  it  being 
thin,  uniform,  color-stable,  and  unaffected  by  changes  of  temperature 
and  climatic  conditions.  Only  breakage  or  scratches  on  the  surface 
will  impair  its  usefulness. 

Color  filters  are  also  prepared  by  coating  gelatin  containing  a 
given  quantity  of  an  organic  dye  upon  optically  flat  and  otherwise 
prepared  glass,  and  after  drying,  stripping  this  film  from  the  glass. 
The  film  is  then  cut  to  any  size  or  shape  and  mounted  between  two 
pieces  of  optically  flat  glass  by  means  of  a  special  cement  (Canada 
balsam)  under  heat  and  pressure.  This  type  of  filter  requires  greater 
care  in  handling  than  the  solid  glass  type.  Improper  handling,  contact 
with  water,  alcohol  or  high  temperatures  will  render  it  useless. 
Humidity  or  exposure  to  direct  action  of  sunlight  also  causes  deteriora- 


tion.  This  type  of  filter  should  never  be  selected  for  use  in  the  tropics 
or  for  sea  travel.  However,  for  use  in  a  temperate  climate,  with  care- 
ful handling,  it  will  prove  entirely  satisfactory.  Gelatin  filters  are 
available  in  a  far  greater  number  of  colors  than  solid  glass  filters,  and 
being  less  expensive,  are  to  be  recommended  for  special  purposes  and 
experimental  work. 

Still  another  type  of  filter  is  obtainable  in  the  form  of  a  so-called 
water  cell,  which  consists  of  a  glass  container  having  two  parallel 
sides  filled  with  distilled  water  into  which  the  dye  required  is  dis- 
solved. This  type  of  filter  is  used  especially  in  scientific  work,  such  as 
photomicrography,  where  it  acts  not  only  as  a  color  filter,  but  also  as 
a  heat  absorption  filter.  It  is  placed,  not  between  the  lens  and  the 
photographed  subject,  but  between  the  latter  and  the  light  source. 

For  the  purpose  of  general  Leica  photography,  we  are  concerned 
only  with  the  first  two  types  of  filters,  either  of  which  may  readily  be 
slipped  on  and  off  the  lens  of  the  camera.  Of  these  two,  the  solid  glass 
type  filter  is  much  the  better  for  the  Leica  camera  on  account  of  port- 
ability. Gelatin  filters  have  a  definite  place  in  the  kit  of  the  experi- 
mentally-minded worker,  or  one  whose  specialized  work  calls  for  an 
endless  variety  of  filters  for  tests  and  for  other  specific  purposes. 

Solid  glass  filters  are  to  be  preferred  not  only  because  of  greater 
stability  and  permanence,  but  also  because  of  simplicity.  Any  medium 
transmitting  light  affects  its  course  to  a  greater  or  lesser  degree, 
depending  upon  whether  it  is  optically  flat.  If  it  is,  the  disturbance 
is  negligible.  s  The  greater  the  number  of  media  the  light  has  to 
traverse,  the  greater  the  disturbance  of  its  course.  Thus,  when  light 
penetrates  thin  solid  glass,  it  is  affected  only  by  the  process  of  enter- 
ing it  on  one  side,  traversing  its  dyed  mass  and  emerging  on  the  other 
side.  Pure  gelatin  filters  used  without  mounting  between  glass  would 
be  just  as  effective  were  it  possible  to  handle  them  in  such  form.  But 
a  gelatin  filter,  cemented  between  two  pieces  of  glass,  requires  the 
light  to  pass  through  glass,  Canada  balsam,  gelatin,  Canada  balsam 
and*  glass  again.  Obviously  it  is  simpler  to  produce  a  filter  with  two 
piano-parallel  (optically  flat)  surfaces  than  one  possessing  ten  sur- 
faces meeting  this  requirement.  Of  course,  this  is  merely  a  theo- 
retical, rather  than  a  practical,  objection,  but  it  is  frequently  con- 
firmed in  practice  resulting  in  pictures  of  lesser  sharpness  and  poorer 

As  a  matter  of  fact,  it  should  be  known  that  filters  actually  affect 
the  sharpness  of  the  picture,  the  type  of  the  filter  merely  accounting 



Fig.  61    Summer  Solitude  John  L.  Davenport 

Elmar  50mm,  1/100  second  at  f :4.5.     Filter:  23A,  Du  Pont  Superior  Film 

for  the  degree  of  unsharpness.  Theoretically  speaking,  the  shorter 
the  wave-length  of  light,  the  sharper  the  image.  Violet  and  blue 
light,  having  the  shorter  wavelengths,  are  capable  of  producing 
sharper  images.  If  a  dense  filter  is  used  which  holds  back  the  entire 
amount  of  blue  light,  it  permits  only  that  light  which  has  the  longer 
wave  length  to  reach  the  film,  with  the  resulting  decrease  in  sharp- 
ness of  the  image.  Moreover,  some  lenses  are  not  so  well  corrected 
for  light  of  the  longer  wave  length  so  that  they  cannot  yield  relatively 
as  sharp  an  image  as  that  obtainable  in  the  presence  of  blue  rays. 
In  other  words,  the  use  of  filters  results  in  pictures  of  lesser  sharpness 
because  the  very  element  which  contributes  most  to  sharp  images 
has  been  eliminated  or  weakened. 

What  has  been  said  about  filters  and  their  effect  upon  sharpness 
of  images  should  not  be  taken  too  literally.  For  practical  purposes, 
the  effect  of  a  good  filter  upon  the  sharpness  of  the  image  is,  as  a 
matter  of  fact,  quite  negligible.  Most  of  the  objections  are  of  a 
theoretical  nature  based  upon  careful  and  painstaking  comparisons 
made  under  the  microscope.  The  purpose  of  these  objections  is  not 
so  much  to  discourage  the  use  of  filters  as  to  produce  a  more  in- 


their  products  which  gradually  make  the  use  of  filters  less  essential. 

When  Faters  Should  Be  Used 

Filters  can  and  should  be  used  if  their  choice  and  application 
are  made  judiciously  and  not  indiscriminately.  They  are  intended  to 
establish  and  correct  contrasts  between  various  degrees  of  brightness 
in  the  picture.  The  human  eye  has  the  ability  to  distinguish,  not 
only  between  light  and  dark,  but  also  between  colors.  Colors  pro- 
duce the  sensation  of  various  degrees  of  brightness.  Since  color 
cannot  be  rendered  through  black  and  white  photography,  we  make 
it  reproduce  our  sensations  of  the  varying  degrees  of  brightness  in 
terms  of  black,  white  and  intermediate  shades  of  gray.  To  com- 
pensate for  the  inability  of  the  film  to  interpret  things  in  terms  of 
telligent  and  judicious  attitude  towards  their  application  in  Leica 
photography.  Our  nearest  photographic  relatives,  the  cameramen  of 
Hollywood,  using  almost  the  same  negative  material,  employ  filters 
extensively.  But  their  results  tend  only  to  confirm  what  has  been 
said:  their  knowledge  of  emulsions,  plus  their  knowledge  of  filters, 
yield  results  of  rare  excellence  and  quality. 

It  may  not  be  amiss  to  qualify  filters  as  the  " necessary  evil"  of 
miniature  photography.  They  are  something  to  be  used  if  absolutely 
necessary,  but  it  would  be  better,  whenever  possible,  to  do  without 

Undoubtedly,  this  very  feeling  prevailing  among  photographers 
causes  manufacturers  of  film  to  strive  for  those  characteristics  in 
degrees  of  brightness  as  does  the  eye,  we  use  filters.  It  is  important 
to  realize  that  ordinarily  we  would  need  no  filters  if  the  film  repro- 
duced colors  at  the  same  scale  of  tonal  values  as  the  eye  sees  them. 
This  is  important  because  film  manufacturers  strive  to  approach  this 
millenium,  and  modern  film  materials  require  the  use  of  filters  to  a 
much  lesser  degree  than  the  older  types  of  film. 

Basically,  color  filters,  as  used  in  photography,  can  serve  a  two- 
fold purpose:  to  establish  the  balance  of  color  values,  or  to  upset 
that  balance.  When  the  contrast  between  the  various  degrees  of 
brightness  in  the  pictures  approximates  that  perceived  by  the  eye — 
the  balance  is  considered  established.  Depending  upon  the  emulsion 
used,  it  is  then  normal  or  corrected,  When  the  contrast  between  the 
various  degrees  of  brightness  is  rendered  differently  from  the 
visual  perception — it  is  said  that  the  color  values,  interpreted  in 
terms  of  shades  of  gray,  are  undercorrected  or  overcorrected.  A 
black  sky  or  a  dark  gray  sky  with  white  clouds  in  a  midsummer 
landscape  is  an  example  of  overcorrection,  while  a  white  sky  with 



light  gray  clouds  in  a  similar  picture  would  indicate  under  correction. 
An  intentional  upsetting  of  the  balance  of  color  values  may  lead  to 
attractive  effects.  But  the  practice  should  not  become  a  mania. 

To  be  able  to  use  niters  correctly,  to  make  them  fill  a  definite 
need  and  perform  a  definite  task,  the  photographer  must  know  the 
film  he  uses,  know  its  sensitivity  to  colors,  know  which  colors  react 
more  strongly  on  its  emulsion  and  which  should  be  suppressed  and 
retarded  so  that  other  colors  may  become  equally  effective.  This, 
in  effect,  is  nothing  less  than  handicapping  one  or  more  of  the  more 
actinically  active  colors  in  favor  of  those  which  are  ''slow  in  getting 
there.77  Thus,  if  the  film  records  blue  too  freely,  some  of  it  should 
be  held  back.  A  yellow  filter  is  used  for  this  purpose. 

A  panchromatic  film  is,  generally  speaking,  more  evenly  balanced, 
in  its  response  to  colors,  but  its  sensitivity  to  green  is  slightly  lower 
than  to  other  colors.  To  effect  balance,  all  other  colors  must  be 
suppressed  or  retarded  slightly  in  order  to  give  the  green  color  an 
opportunity  to  impress  itself  on  the  film.  A  certain  greenish  colored 
filter  is  used  for  this. 

The  effect  which  filters  have  upon  certain  emulsions  may  be 
clearly  understood  from  the  diagrams  shown.  These  are  not  accurate, 
but  they  tend  to  interpret  the  color  sensitivity  of  different  emulsions 
when  a  filter  is  placed  in  front  of  a  lens. 

Fig.  62     Effect   of   Filters   upon  Relative    Color    Sensitivity   of   Film:    A 
Typical  Orthochromatic  Emulsion   (in  Daylight) 


In  considering  the  use  of  filters,  it  is  most  important  to  realize 
that  even  films  of  the  same  type  but  of  various  makes  have  different 
characteristics  regarding  their  degree  of  sensitivity  to  different  colors. 
Thus,  an  orthocliromatic  film  of  one  make  will  respond  to  certain 
colors  to  a  different  degree  than  an  orthochromatic  film  of  another 
make.  The  same  applies  to  various  makes  of  panchromatic  films. 

Fig.  63  Effect  of  Filters  upon  Relative  Color  Sensitivity  of  Film:  A 
Typical  Orthochromatic  Emulsion  (in  Mazda  Light) 

Nearly  every  film  manufacturer  publishes  spectrographs  of  his  re- 
spective emulsions,  which,  if  properly  read,  indicate  their  relative 
sensitivity  to  color.  Some  manufacturers  have  this  information  avail- 
able in  the  form  of  numerical  tables  showing  the  relative  sensitivity  in 
terms  of  per  cent,  100  standing  for  " normal7 '  color  rendering. 

The  Agfa  Ansco  Company  offers  the  following  information  concerning 
color  sensitivity  as  measured  by  the  Agfa  Step  Color  Chart  for  the  same 

•  Red         Yellow        Green         Blue 

In  daylight    60  50  30  140 

In  Mazda  light 180  80  40  80 

On  the  other  hand,  manufacturers  of  filters  supply  spectrophotometric 
absorption  curves  of  filters  which  show  graphically  colors  which  are  trans- 
mitted and  absorbed  by  a  given  filter.  A  combined  study  of  these  data 
will  yield  accurate  information  as  to  what  results  may  be  expected  from 
the  use  of  certain  filters  in  connection  with  certain  films.  This  informa- 
tion, however,  is  not  essential  for  the  use  of  filters  except  in  work  of  a  very 
exacting  nature.  For  general  use,  working  familiarity  with  a  film  and 
filter  may  be  gained  by  more  practical  methods. 



Fig.  64     Effect  of  Filters  upon  Relative  Color  Sensitivity  of  Film:   Typical 
Panchromatic  Emulsion  of  Medium  Sensitivity  to  Red  (in  Daylight) 

Making  Your  Own  Filter  Tests 

If  a  working  knowledge  of  the  properties  of  a  film  or  filter  is  desired, 
a  series  of  exposures  on  the  film  with  and  without  the  filter  is  the  best 
means  of  getting  it.  Such  exposures  should  be  made  with  great  care  and 

Fig.  65     Typical  Panchromatic  Emulsion  of  Medium  Sensitivity  to  Red  (in 
Mazda  Light) 


a  record  of  conditions  kept.    The  first  exposure  should  be  made  without  the 
filter  and  should  be  based  upon  a  careful  reading  of  a  reliable  exposure 
meter.    The  series  of  exposures  should  be  carried  out  according  to  a  defi- 
nite plan: 
Film: Rated  Speed: 


.  Daylight 


Meter          Lens 
Reading    Aperture 
1  sec.          f/6.3 

1  second 




2  seconds 





4  seconds 

4  Blank 





*/2  second 





l/4  second 

7  Blank 



No.  2 

I  sec.             " 

2  seconds 




4  seconds 





8  seconds 

11  Blank 




1  second 





1A  second 

Similar  procedure  may  be  employed  for  testing  one  or  two  other  filters. 
The  exposed  film  should  be  developed  in  the  developer  customarily  used. 
The  final  proof  of  the  test  is  in  the  finished  print.  The  best  print  obtain- 
able should  be  made  from  the  negative  resulting  from  Exposure  No.  1. 
Prints  from  all  other  negatives  should  be  made  in  exactly  the  same  way, 
the  same  paper  used,  the  same  degree  of  enlargement,  the  same  exposure 
given,  the  same  developer  and  time  of  development.  When  these  prints 
are  finished  and  dry,  they  should  be  compared  and  studied  for  color  cor- 
rection, contrasts  and  detail  rendering. 

Fig.  66    Effect  of  Filters  upon  Relative  Color  Sensitivity  of  Film:     A 
Typical  Panchromatic  Emulsion  of  High  Sensitivity  to  Red  (in  Daylight), , 



Fig.   67     Effect   of   Filters    upon    Relative   Color    Sensitivity   of   Film:    A 
Typical  Panchromatic  Emulsion  of  High  Sensitivity  to  Red  (in  Mazda  Light) 

Such  study  will  frequently  yield  surprising  results.  It  may  be  found, 
for  instance,  that  best  results  may  be  obtained  without  the  filter.  Or  that 
the  most  desirable  effect  was  produced  when  the  filter  was  used  without 
increase  of  exposure.  And  then  again,  it  may  be  that  the  picture  was 
most  interesting  when  no  filter  was  used,  but  the  exposure  halved. 

Thus,  for  instance,  it  will  be  found  by  actual  experience  that  if  a 
filter,  primarily  intended  to  suppress  blue  rays  for  which  a  given  film  is 
too  sensitive,  is  being  used  effectively  in  daylight,  the  same  filter  will  be 
found  unnecessary  for  work  in  artificial  light  because  of  its  more  abundant 
yellow  and  red  rays.  Obviously,  there  is  no  need  to  filter  blue  rays  from 
a  light  which  is  in  itself  deficient  in  that  color.  The  same  would  hold 
true  of  work  in  the  late  afternoon  when  daylight  becomes  more  profuse 
in  yellow  light.  There  would,  ordinarily,  be  no  need  for  a  yellow  filter. 
It  must  be  remembered,  however,  that  although  a  filter  is  used  to  establish 
a  definite  balance  of  color  rendering,  the  use  of  the  filter  is  superfluous 
where  that  balance  is  present  either  in  the  light  source  or  the  subject. 
Thus,  if  the  sky  is  dark  blue,  even  a  light  yellow  filter  will  create  a  cor- 
rect color  balance  on  a  panchromatic  film,  and  if  it  be  a  panchromatic 
emulsion  of  high  red  sensitivity,  no  filter  will  be  required  to  produce  such 
balance.  If  the  sky,  however,  be  pale  blue  or  grayish  blue,  a  more  dense 
filter  would  be  required. 

Filter  Factors 

To  identify  filters  by  means  of  their  respective  factors  would  be 
meaningless,  since  no  filter  requires  the  same  increase  of  exposure  for 
every  film  and  for  every  light  condition.  For  this  reason,  modern  filters 
are  no  longer  designated  by  the  symbol  "x"  following  a  number,  like  2x, 
3x,  4x,  etc.  These  designations  were  intended  to  represent  the  inc  mse 
of  exposure  by  two  times,  three  and  four  times,  respectively.  Modern 
filters  are  designated  by  their  manufacturers  either  by  a  letter,  number 


or  both,  and  each  represents  a  medium  of  definitely  known  power  of  ab- 
sorption or  transmission  of  certain  rays  of  light.  Consequently,  filter 
factor  tables  should  not  be  taken  too  literally,  for  the  best  of  them  are 
merely  intended  to  give  their  relative  power  of  absorption  or  transmission 
regarding  a  definite  emulsion.  These  tables  should  be  used  as  guides  only. 
A  definite  familiarity  with  the  properties  of  a  film  can  be  gained  only 
through  practical  application  very  much  in  the  same  measure  as  is  the 
case  with  emulsions,  developers,  papers,  lenses,  etc. 

While  color  filters  properly  used  offer  a  very  flexible  and  definite 
control  of  contrasts  and  tones,  it  should  be  realized  that  there  are  other 
means  with  which  certain  effects  may  be  produced.  The  making  of  prints 
by  enlarging  rather  than  by  contact  offers  an  opportunity  for  holding 
back  the  light  from  certain  areas  of  the  print  while  permitting  it  to 
print  through  on  other  areas.  This  dodging  or  shading  by  means  of  a  mov- 
ing hand,  finger,  piece  of  black  paper,  or  cardboard  enables  the  skilled 
worker  to  produce  quite  remarkable  effects  on  the  finished  print.  Thus, 
for  instance,  if  one  has  a  negative  of  a  landscape  on  which  a  filter  has  not 
been  used,  a  negative  possessing  all  detail  and  gradation  in  the  foreground 
but  a  corresponding  overexposure  and  whiteness  of  the  sky,  the  latter  may 
be  successfully  printed  in  or  darkened  to  any  degree  desired  by  first  expos- 
ing the  paper  for  a  length  of  time  sufficient  to  bring  out  the  detail  of  the 
foreground  and  then  interposing  a  piece  of  cardboard  between  the  lens  of 
the  enlarger  and  the  portion  of  the  paper  containing  foreground,  letting 
the  sky  print  through.  The  exact  technique  of  dodging  and  shading  is  de- 
scribed elsewhere.  This  point  is  mentioned  here  to  assist  any  who  may 
have  neglected  to  use  a  filter  and  who  wish  to  improve  a  picture  which 
would  otherwise  appear  bare  and  uninteresting  from  lack  of  an  appropri- 
ate sky  background. 

Choice  of  Film  and  Filter 

Those  who  lack  experience  in  selecting  a  film  and  a  filter  to  go  with 
it  to  produce  certain  effects  will  be  well  served  with  Viewing  Filters. 
These  are  strictly,  as  their  name  implies,  visual  filters  and  should  never 
be  used  for  actual  photography.  They  consist  of  discs  or  squares'  of  col- 
ored glass  or  gelatin  mounted  between  glass.  Colors,  when  viewed 
through  them,  are  considerably  dulled  and  impress  the  eye  in  terms  of 
their  relative  brightness  and  contrast  of  tone,  approximating  the  interpre- 
tation of  the  film.  These  visual  filters  are  available  in  the  form  of 
monocles,  or  regular  spectacles.  By  looking  through  them,  the  photog- 
rapher is  in  a  position  to  anticipate  the  effect  upon  the  film  before  ex- 
posure. For  work  on  ortho chromatic  emulsions  deep  blue  filters  are  used, 
while  panchromatic  emulsions  require  either  a  muddy  yellow  or  greenish 
visual  filter.  By  far  the  most  practical  and  economical  visual  filter  guide 
for  the  purpose  can  be  had  in  the  form  of  an  inexpensive  Filter  Test  Chart, 
furnished  by  the  Eastman  Kodak  Company.  This  chart  contains  eight 
transparent  samples  of  the  most  popular  contrast  filters  and  four  test 
filters  (blue,  green,  yellow  and  red)  through  which  subjects  may  be  viewed. 

If  the  subject,  as  seen  through  the  monochromatic  filter,  appears  to 
the  eye  so  that  one  can  distinguish  the  different  degrees  of  brightness  of 
the  various  colors,  the  film  and  filter  indicated  under  that  viewing  filter 
should  be  used  to  secure  such  rendering.  If  one  cannot  distinguish  the 
various  colors,  the  subject  should  be  viewed  through  another  filter,  and  so  on. 
One  of  these  will  be  found  to  give  the  desired  color  correction.  Consider- 
able knowledge  of  rendering  color  contrasts  may  be  gained  from  frequent 
application  of  this  simple  device. 



Fig.  68     Suburban  Home 

Henry  M.  Lester 

Elmar  35mm,    1/60  second  at  f:9.      Sky  Filter.     Du  Pont  Superior  Film 

What  Filters  to  Use 

It  is  a  good  policy  to  follow  the  suggestions  of  manufacturers 
of  photographic  equipment  as  to  the  type  of  accessories.  They  can 
very  well  bear  the  responsibility  for  such  use  as  it  is  to  their  interest 
to  help  obtain  the  best  results  possible.  Choice  of  the  type  and  make 
of  filters  used  should  be  based  upon  the  negative  material  employed. 
If  a  variety  of  films  is  used,  one  will  be  best  served  by  the  compre- 
hensive line  of  solid  glass  filters  offered  by  the  makers  of  the  Leica 
camera.  These  filters  are  of  excellent  quality,  thin,  uniform  and  well 
mounted.  The  filter  mounts  are  important,  particularly  when  the 
camera  is  to  be  used  in  connection  with  the  various  accessories  and 
attachments  for  which  these  mounts  are  designed.  For  special  pur- 
poses, and  for  specific  work  with  Eastman  Kodak  emulsions,  the 
Wratten  Light  Filters  (gelatin  mounted  between  glass)  should  be 
used,  they  being  also  of  excellent  quality  and  easily  available  in 
unmounted  circles  fitting  the  Leica  Filter  mounts.  The  Wratten 
Light  Filters  are  especially  designed  for  Eastman  emulsions  artd  the 
most  comprehensive  information  is  available  on  their  effect  on  these 


One  would  be  well  served  with  a  complete  line  of  Leica  niters 
to  which  special  "Wratten  Light  Filters  may  be  added  as  required. 
However,  an  impressive  array  of  niters  is  not  needed  to  turn  out 
excellent  pictures.  One  or  two  should  be  sufficient  for  all  general 
work  with  modern  film  emulsions.  The  writers  know  of  several  work- 
ers who  boast  of  many  an  excellent  picture  but  of  only  one  filter. 

Those  who  prefer  orthochromatic  films  will  be  able  to  go  through 
life  with  but  one  or  two  filters  without  missing  anything.  Leitz  No.  1 
would  be  the  best  choice,  while  No.  2  might  be  added  to  complete  the 
outfit.  The  addition  of  a  Graduated  Sky  Filter  might  be  included 
sometimes  in  preference  to  the  No.  1.  The  equivalent  of  these  are 
the  Wratten  Kl  and  Wratten  K2. 

Users  of  Panchromatic  Films  may  use  more  filters,  but  only  if  the 
scope  of  their  work  is  greater.  Besides  the  two  filters  mentioned 
above,  together  with  possibly  the  Sky  Filter,  the  Green  Panchromatic 
Filter  should  be  used.  If  Eastman  panchromatic  emulsions  are  em- 
ployed, instead  of  the  Leitz  Panchromatic  Filter,  the  Wratten  XI  (for 
day  light)  or  the  Wratten  X2  (for  artificial  light)  should  be  used. 

The  Leitz  Infra  Red  Filter  is  a  special  filter  which  should  be  used 
in  connection  with  the  Infra  Red  films  for  special  effects.  It  is  one 

Fig.  69    The  Tower 

Blmar  35mm  lens,  f  :9,  1/60,  dark  yellow  filter,  Agfa  Superpan. 


Ernst  Schwarz 


of  those  filters  which  for  special  reasons  emphatically  upsets  the  color 
balance.  The  Wratten  line  offers  a  complete  assortment  of  red  niters, 
ranging  from  very  pale  red  to  such  densities  as  do  not  transmit  visible 
light.  The  choice  of  the  density  should  be  governed  by  the  purpose 
for  which  it  is  intended. 

A  special  filter  is  made  by  the  Leitz  Company  for  elimination  of  in- 
visible ultra  violet  rays  adjoining  the  visible  range  of  the  spectrum. 
These  filters  are  intended  for  use  only  in  high  altitudes  where  these  rays 
are  abundant.  At  sea-level  invisible  ultra  violet  rays  are  not  sufficient  to 
be  detrimental.  In  small  amounts  they  are  not  effective,  being  actually 
filtered  out  by  the  glass  of  the  lens  itself.  Never  use  a  filter  unless  one 
is  required  to  eliminate  something  that  is  not  wanted  in  the  pictures.  With 
particular  reference  to  the  Ultra  Violet  Filter,  commonly  known  as  the 
U.  V.  Filter,  it  should  be  remembered  that  if  the  filter  holds  back  only 
certain  rays,  the  effect  of  which  we  want  to  suppress  in  the  pictures, 
whereas  it  freely  transmits  all  other  rays,  the  exposure  need  not  be  in- 
creased to  compensate  for  that  filter,  since  those  colors  that  will  result  in 
underexposure  are  being  deliberately  so  treated  by  the  very  use  of  the 
filter.  The  same  may  apply  to  some  other  filters,  particularly  those  pale 
yellow,  pale  green  and  pale  blue  filters  which  are  used  for  very  slight  color 
correction.  While  actually  even  clear  glass  filters  require  a  theoretical 
increase  of  exposure  (about  8%),  this  may  easily  be  disregarded  because 
of  the  available  latitude  of  the  film  and  the  improbability  of  getting  a  100% 
correct  exposure  at  all  times. 

Some  of  the  red  filters,  like  the  Wratten  A  or  F  may  be  used  for 
many  purposes.  Although  they  are  not  strictly  infra-red  filters,  since 
they  do  transmit  a  good  portion  of  the  visible  part  of  the  spectrum,  they 
will  produce  effects  quite  similar  to  those  obtainable  with  the  regular 
infra-red  filters  when  used  in  connection  with  Infra-Red  films.  It  will 
be  simply  a  matter  of  degree,  but  the  exposure  will  be  substantially 
shorter.  These  red  filters  are  frequently  known  as  effect  filters  because 
they  are  used  to  produce  most  striking  effects  of  night  scenes,  moonlight 
scenes  in  broad  daylight.  In  addition,  these  filters  are  also  known  as 
haze-filters  because  they  have  the  rare  property  of  eliminating  aerial  haze 
in  distance  photography,  and  in  aerial  photography.  It  should  be  remem- 
bered, however,  that  while  these  filters  are  very  effective  in  eliminating 
aerial  haze,  they  -will  not  cut  through  air  filled  with  smoke,  dust,  fog 
or  steam. 

While  speaking  of  effect  filters,  the  so-called  fog-filters  should  be 
mentioned.  These  fog  filters,  unlike  the  haze-filters,  are  not  used  to 
eliminate  fog  from  pictures,  but,  on  the  contrary,  to  put  it  into  the  picture! 
Fog-filters  are  decidedly  misnamed.  They  are  not  filters  but  merely  dif- 
fusion screens,  which  are  available  in  a  number  of  degrees  of  softness  or 
fog.  In  skilled  hands,  these  fog-filters  produce  truly  remarkable  results. 
But,  as  a  matter  of  general  practice,  their  use  is  not  to  be  recommended. 
The  small  Leica  negative  should  remain  as  sharp  as  possible.  If  softness 
is  desired,  it  should  be  produced  by  means  of  illumination  or  by  using  an 
appropriate  lens  at  the  proper  opening.  All  kinds  of  fog,  and  all  degrees 
of  softness  and  diffusion  may  be  produced  on  the  finished  print  by  skillful 
manipulation  of  the  enlarger,  and  the  reader  is  cautioned  against  placing 
too  much  faith  in  such  filters  as  are  entirely  satisfactory  for,  say,  motion 
picture  work,  but  barely  desirable  in  Leica  photography. 


Just  when  to  use  a  filter  is  often  something  of  a  mystery  to  a  begin- 
ner. Obviously,  it  is  a  matter  of  that  great  combination  of  knowledge, 
experience  and  judgment.  In  order  to  assist  the  beginner,  the  following 
list  is  offered: 

Yellow  Filters:  May  be  used  with  either  ortho  or  pan  films.  Everything 
else  being  equal,  a  denser  yellow  filter  should  be  used  with  the  ortho 
than  with  the  pan  film.  These  filters  are  almost  exclusively  for  cloud 
effects  upon  light  blue  skies.  The  lighter  the  sky  the  darker  should 
be  the  filter. 

Sky  Filters:  For  use  with  all  films.  This  filter  has  a  lower  half  of  clear 
glass,  which  from  the  center  gradually  changes  into  a  yellow  upper 
half.  The  purpose  of  this  filter  is  to  hold  back  the  blue  rays  emanat- 
ing from  the  sky  only,  without  affecting  the  lower  half  of  the  image 
in  any  way.  It  requires  no  increase  of  exposure.  One  should  be  care- 
ful in  using  this  filter  that  the  center  of  the  picture  coincides  with  the 
line  of  the  horizon.  A  most  useful  filter  for  landscapes  and  seascapes. 

Green  Panchromatic  Filters:  A  filter  specifically  designed  to  enhance  the 
comparatively  low  sensitivity  to  the  green  of  panchromatic  films.  Its 
effect  upon  a  panchromatic  emulsion  is  similar  to  that  of  a  yellow 
filter  upon  an  orthochromatic  emulsion.  It  holds  back  not  only  the 
blue,  but  also  the  red,  to  which  this  type  of  film  is  very  sensitive.  It 
is,  therefore,  useful  in  the  same  way  for  cloud  effects,  etc.  Whenever 
Eastman  panchromatic  films  are  used,  Wratten  green  panchromatic 
filters  are  recommended  for  best  results.  (XI  for  daylight  work  and 
X2  for  artificial  light.) 

U.  V.  Filter:  To  be  used  only  in  high  altitudes,  mountains,  etc.  Not  for 
work  from  an  airplane  when  photographing  the  earth!  The  layer  of 
air  acts  as  an  efficient  U.  V  Filter.  This  filter  does  in  the  mountains 
what  a  denser  (yellow)  filter  does  at  sea  level. 

Red  Filters:   For  extreme  contrasts  and  effects,  where  overcorrection  is 

intentionally  aimed  for  in  order  to  produce  dramatic  effects.  Brilliant 
white  clouds  against  a  black  sky.  Moonlight  effects  with  the  sun  sub- 
stituting for  the  moon.  Dramatic  sunsets.  To  be  used  with  pan- 
chromatic films  only.  The  darker  red  filters  are  designed  and  intended 
specifically  for  infra  red  photography  with  Infra  Red  film. 

Editor's  Note. 

Our  readers  will  be  interested  to  know  that  filters  having  transmission 
characteristics  and  factors  similar  to  those  of  the  Wratten  type,  are  now 
available  in  many  of  the  popular  colors  in  solid  glass  form.  These  filters 
are  made  of  optically  flat  glass  not  affected  by  temperature  or  climatic 
conditions.  They  are  distributed  in  this  country  by  the  Chess- United  Co., 
160  Fifth  Avenue,  New  York  City,  through  their  agents  and  dealers. 

Filter  Factor  Table 

The  following  table  of  filter  factors  is  offered  in  the  hope  that  it  be 
used  with  a  grain  of  salt.  It  is  deliberately  placed  at  the  end  of  the  chap- 
ter, trusting  that  the  reader  will  not  use  it  literally,  but  merely  refer  to 
it  for  general  guidance  and  information.  The  factors  are  bound  to  change 
with  varying  light  conditions.  They  should  not  be  followed  blindly,  but 
when  used  intelligently  may  be  helpful  in  getting  the  desired  results. 




Fig.  71    Moon  Over  the  Empire  State 

ELmar  50mm,   3   seconds  at  f:3.5.     Photograph  taken   at  1   A.M. 

John  T.  Moss,  Jr. 

DuPont  Superior  Fihn 


THE  35  MM 


The  35mm  film  used  in  standard  motion  picture  cameras  estab- 
lishes for  the  Leica  a  valuable  relationship.  Because  of  the  vast 
quantities  of  film  which  the  motion  picture  industry  consumes,  the 
manufacturers  of  35mm  film  go  to  no  end  of  trouble  to  produce  the 
greatest  variety  and  finest  quality  of  film.  This  in  turn  makes  avail- 
able to  the  Leica  user  an  unlimited  choice  of  negative  material  which 
the  user  of  larger  cameras  does  not  enjoy.  "While  this  is  a  decided 
advantage  to  an  experienced  Leica  worker,  it  is  frequently  confusing 
to  the  beginner. 

It  may  be  said,  almost  without  reservation,  that  the  modern 
35mm  film  produced  by  large  manufacturers  is  of  excellent  uniform 
quality  throughout,  regardless  of  its  type.  However,  not  all  films 
are  adapted  to  every  kind  of  work.  If  they  were,  there  would  prob- 
ably be  no  need  for  some  fifty  different  types  of  35mm  film  available. 
Some  film  emulsions  have  a  wide  range  of  application  and  may  be 
•considered  more  or  less  universal.  The  word  universal  is  obviously 
a  generality  and  as  such  is  only  measurably  correct.  Other  films  are 
designed  to  fill  a  specific  need  in  the  more  specialized  fields  of 

Those  Leica  workers  who  do  not  concentrate  upon  the  more 
specialized  phases  of  photography,  like  photomicrography,  aerial 
photography,  elinical  work,  etc.,  but  who  want  to  obtain  excellent 
photographs  within  the  scope  accessible  to  all  photographic  workers, 
will  find  that  almost  any  good  film  of  a  standard  make  will  answer 
their  requirements — provided  they  will  get  to  know  it  through  con- 
stant use  and  will  understand  its  characteristics  and  its  response 
to  exposure  and  development.  On  the  other  hand,  those  who  are 
doing  specialized  work  should  select  a  film  to  answer  that  specific 
purposp.  In  either  case,  for  consistently  good  results,  once  a  film 
emulsion  is  decided  upon,  whether  it  be  for  portraiture,  pictorial 
work  or  copying  X-rays,  that  film  should  be  used  always  for  that 
purpose,  to  the  exclusion  of  all  others, 


Success  in  photography,  as  in  all  other  crafts,  is  based  upon  the 
ability  of  the  worker  to  produce  definite  results.  To  produce  them 
consistently  the  worker  must  know  Ms  equipment  and  materials 
thoroughly  to  make  them  do  what  he  wants.  Therefore :  know  your 
film,  learn  what  it  can  do  and  make  it  fit  your  purpose. 

Part  I  — Film  Selection 

The  35mm  films  should  be  considered  from  the  following  view- 
points as  the  first  step  in  making  the  selection : 

1.  Sensitivity  to  Color    .     .    .    From  this  viewpoint  the  films  are 
considered  depending  upon  their  response  to  various  colors. 
Those  that  respond  or  are  sensitive  to  all  colors  including  red  are 
known  as  Panchromatic. 

Those  that  are  sensitive  to  all  colors  except  the  spectral  red  are 
known  as  Orthochromatic. 

The  relative  sensitivity  of  an  emulsion  to  the  various 

colors  can  be  controlled  by  means  of  filters. 

Films  that  are  not  sensitized  to  distinguish  between  colors,  except 
between  black  and  white,  are  known  as  Color-Blind. 
Then  there  are  the  Special  Emulsions  required  for  color  photog- 
raphy infra-red  photography  or  direct  positives. 

2.  Speed  of  Emulsion    .     .     .    From  this  angle  the  films  are  con- 
sidered depending  upon  the  relative  amount  of  light  required  to 
form  an  image  on  the  emulsion.     This  classification  results  in 
terming  films  as  fast,  medium  or  slow. 

The  speed  of  a  given  emulsion  can  be  controlled 
within  certain  limits  by  development. 

3.  Graininess    .     .     .    From  this  point  of  view  the  films  are  con- 
sidered depending  upon  the  size  of  the  grain  of  the  emulsion. 
The  smaller  the  size  of  the  grain,  the  more  desirable  the  emulsion 
for  Leica  work. 

Although  the  size  of  the  grain  is  inherent  in  each 
emulsion,  being  a  definite  part  of  its  structure,  its  final 
size  in  the  negative  can  be  controlled  by  means  of  suit- 
able development. 

4.  Contrast    .    .    .    From  this  viewpoint,  we  consider  the  emulsions 
as  to  their  ability  to  render  comparative  degrees  of  brightness 
of  the  image.    If  the  film  is  capable  of  rendering  many  shades  or 
gradations  of  grays  between  black  and  white,   it  is  known  as 
a  low  contrast  or  long  scale  film.    If  the  range  of  gradations  of 


Film  Selection 

Fig.*  72     I  Smell  Cat! 

Fig.  73     Ah,  There  You  Are! 

Roland  Smith 

Roland  Smith 

gray  between  black  and  white  is  not  great,  the  emulsion  is  known 
as  one  of  high  contrast  or  short  scale.     Generally,  the  finer  the 
grain  the  greater  the  contrast  and  the  shorter  the  scale. 
Although  contrast  is  substantially  built  into  the  emul- 
sion, it  can  be  most  effectively  controlled  by  exposure 
and  development  skilfully  made  to  depend  upon  each 

5.  Latitude  .  .  .  Here  we  consider  the  film  by  its  ability  to  react 
to  various  quantities  of  light  admitted  to  it.  It  would  be  just  too 
bad  if  every  exposure  would  have  to  be  "on  the  button",  so  to 
speak,  to  produce  a  usable  negative.  We  therefore  look  to  the 
emulsion  for  its  ability  to  yield  usable  negatives  with  a  certain 
amount  of  under  or  overexposure.  Latitude  is  important  to  us 
not  only  because  of  the  ever  present  danger  of  over  or  under- 
exposure, but  also  because  of  the  definite  effect  which  we  fre- 
quently want  to  produce  by  over  and  underexposure.  Generally, 
the  finer  the  grain  of  an  emulsion,  the  less  its  latitude. 

The  latitude  of  the  film  is  one  of  its  inherent  charac- 
teristics which  cannot  be  readily  controlled. 

Selection  to  Fit  the  Purpose 

An  important  factor  of  successful  Leica  photography  which  is 
not  generally  appreciated  and  understood  is  the  necessity  to  choose  a 
film  to  fit  a  definite  purpose. 

The  general  level  of  quality  of  Leica  work  could  be  raised  con- 
siderably if  the  worker,  instead  of  asking  the  dealer  for  the  best  and 
most  expensive  film,  would  consider  these  questions : 

What  is  the  film  going  to  be  used  for? 

In  what  developer  will  the  film  be  processed? 

What  size  enlargements  will  be  required? 

What  type  of  paper  will  the  enlargements  be  printed  on  (glossy, 

mat,  rough)  ? 

The  size  of  the  grain,  as  is  generally  known,  increases  with  the 
speed  of  the  emulsion.  There  is  a  vast  field  of  photography  where 
extreme  speed  of  the  film  is  not  as  essential  as  fineness  of  grain.  The 
selection  of  the  emulsion  should  therefore  be  made  with  a  preference 
for  fine  grain  rather  than  speed.  This  is  made  quite  feasible  by  the 
growing  availability  and  popularity  of  extremely  fast  and  sharp 
lenses.  However,  where  sufficient  light  is  not  available,  or  quick 
action  must  be  recorded,  fast  films  must  be  used  and  one  must  be 
willing  to  sacrifice  the  size  of  the  grain  and  be  satisfied  with  a  smaller 
enlargement  for  the  sake  of  getting  the  picture,  which  would  be  im- 
possible without  the  fast  film. 


Film  Selection 

Types  of  Film 

With  a  view  to  simplification  of  the  multitude  of  emulsions  avail- 
able on  the  market,  a  classification  into  five  groups  is  offered.  It 
should  be  remembered  that  while  each  of  these  grouped  emulsions 
has  its  own  distinctive  characteristics,  they  have  a  good  deal  in 
common,  and  the  grouping  is  offered  for  simplicity.  Also  as  a  means 
of  expediency,  not  all  the  emulsions  are  being  listed,  but  only  those 
whose  popularity  makes  them  readily  available  in  either  bulk  or 
daylight  loading  packages. 

Group  No.  1     Panchromatic  Emulsions  (Fast) 

Agfa  Superpan 

DuPont  Superior 

Eastman  Kodak  Super-X 

Eastman  Kodak  Super- Sensitive 

Gevaert  Panchromosa 

Perutz  Peromnia,  etc. 

The  films  of  this  group  are  fully  panchromatic,  being  sensitive  to 
all  colors,  including  red.  These  emulsions  are  not  alike  in  their 
relative  response  to  the  various  colors  of  the  spectrum.  For  ex- 
tremely critical  color  corrections  spectrographs  of  each  emulsion 
should  be  consulted.  (These  spectrographs  are  readily  obtainable 
from  the  respective  manufacturers.) 

The  most  distinguishing  feature  of  the  emulsions  of  this  group 
is  their  speed:  their  all-over  great  sensitivity  to  light,  both  daylight 
and  Mazda.  Their  speed  rating  in  daylight  is  23°  Scheiner  or  24  to 
32  "Weston,  and  in  Mazda  light  20°  Scheiner  and  16  "Weston.  The 
emulsions  of  this  group  are  of  the  low  contrast  and  soft  gradation 
type.  The  degree  of  contrast  of  these  films  can  successfully  be  con- 
trolled in  development.  They  possess  excellent  latitude  and  will  yield 
usable  negatives  resulting  from  several  times  under  or  overexposure. 
Their  graininess  is  consistent  with  their  high  speed. 

Group  No.  2     Panchromatic  Emulsions  (Medium  Fast) 

Agfa  Finopan 

DuPont  Micropan 

Eastman  Kodak  Panatomic  * 

Perutz  Perpantic,  etc. 

The  films  of  this  group  are  fully  panchromatic,  the  same  as 
those  in  Group  No.  1,  being  sensitized  to  all  colors.  The  particular 
distinction  of  these  emulsions  is  the  exceptional  fineness  of  grain 
combined  with  good  all-over  sensitivity,  which  places  them  in  the 
medium  fast  class.  Their  speed  rating  averages  from  18°  to  20° 
Scheiner  or  from  8  to  16  Weston  in  daylight,  and  from  14°  to  17° 
Scheiner  or  from  4  to  8  "Weston  in  Mazda  light. 


The  latitude  of  the  films  of  this  group  is  not  as  great  as  that  of 
Group  One  but  still  considerable,  and  can  be  controlled  in  develop- 
ment. Generally,  films  of  this  group  are  of  the  "brilliant'7  type, 
yielding  negatives  of  high  contrast  and  consequently  of  a  shorter 

Group  No.  3    Orthochromatic  Emulsions 

Agfa  Plenachrome 
Gevaert  Express 
Mimosa  Extrema 
Perutz  Neo-Persenso,  etc. 

The  emulsions  of  this  group  are  fine  representatives  of  the 
popular  orthochromatic  type.  They  are  sensitive  to  all  colors,  except 
the  spectral  red,  with  a  high  sensitivity  to  green.  These  films  com- 
bine extreme  fineness  of  grain  with  extreme  speed  to  daylight. 
Their  definition  is  excellent  and  the  gradation  quite  complete.  They 
belong  to  the  " brilliant "  type  characterized  by  high  contrast  and 
a  medium  long  scale.  Their  speed  rating  in  daylight  is  approximately 
Schemer  23°,  Weston  24. 

Fig.  74    Montevideo,  Uruguay 

Burton  Holmes 

Film  Selection 

Group  No.  4    Color-Blind  Emulsions 

This  group  includes  only  positive  film,  which  is  produced  by 
every  manufacturer  of  negative  film.  Positive  film  is  sensitive  only  to 
the  blue  and  violet  colors  of  the  spectrum.  The  distinguishing  fea- 
tures of  positive  film  are  its  extremely  fine  grain,  high  resolving 
power,  excellent  definition  and  extremely  high  contrast.  The  length 
of  its  scale  of  gradation  is  rather  short,  but  this  depends  greatly  upon 
exposure  and  developing  procedure.  The  speed  rating  for  positive 
film  in  daylight  is  about  Scheiner  8°,  "Weston  1.  It  is  difficult  to  give 
its  speed  rating  for  artificial  light  because  it  is  entirely  dependent 
upon  the  amount  of  blue  light  in  the  particular  light  source. 

Group  No.  5     Special  Emulsions 

A.   Films  for  Color  Photography 



DuPont  Bi-Pack 

Eastman  Kodak  Zulcras  Bi-Pack 

Eastman  Kodak  Kodachrome 

Lumiere  Film  Color,  etc. 

Each  of  these  films  represents  a  definite  system  in  itself,  and 

Fig.  75     The  Welder 

Ed.  Schaefer 

complete  information  pertaining  to  their  characteristics  is  beyond  the 
scope  of  this  chapter. 

B.   Infra-Red  Films 

Agfa  Infra-Red 
DuPont  Infra-D 
Eastman  Kodak  K 

These  films  are  panchromatic  with  the  sensitivity  to  red  extend- 
ing beyond  the  visible  red  portion  of  the  spectrum.  Their  sensi- 
tivity extends  to  light  waves  of  from  700  to  1000  millimicrons. 
Without  special  filters  these  films  can  be  used  as  par  speed  pan- 
chromatic emulsions.  It  is  difficult  to  give  the  numerical  speed  rating 
of  these  films  when  used  with  special  infra-red  light  filters.  "Without 
these  special  infra-red  light  filters  they  rate  about  17°  Scheiner  or 
8  Weston,  in  daylight;  but  these  figures  are  to  serve  merely  as  ap- 
proximations. Infra-red  films  are  rather  coarse  grained,  and  their 
gradation,  contrast,  color  properties  depend  largely  upon  the  subject 
matter  and  use  to  which  they  are  put. 

0.   Agfa  Reversible  Superpan 

This  is  an  interesting  new  emulsion  intended  for  direct  positives 
secured  by  reversal.  This  film  cannot  be  developed  to  a  negative. 
It  was  designed  for  direct  production  of  positives  to  be  viewed  as 
stereo  pictures  by  projection  or  by  transmitted  light.  Another  in- 
teresting application  of  this  film  material  is  for  production  of  paper 
negatives  or  enlarged  negatives  by  direct  projection.  Its  speed  rating 
in  daylight  is  20°  Schemer  or  16  Weston,  and  in  Mazda  light  19° 
Scheiner  or  12  Weston.  See  page  126  for  processing  formulas. 

Emulsion  Speed  Values 

Definite  speed  ratings  for  each  emulsion  are  not  given  here.  Speed 
ratings  are  merely  relative  values.  They  are  useful  only  in  connection  with 
given  exposure  meters.  Every  good  exposure  meter  is  accompanied  by  a 
complete  list  of  speed  ratings  of  almost  every  film  known.  One  should 
refer  to  these  lists  for  such  specific  information  and  apply  it  judiciously. 

The  various  emulsion  speed  values  now  used  cannot,  in  general,  be 
compared  directly  with  each  other,  except  possibly  H  &  D  and  the  Weston 
speed  values,  for  the  reason  that  they  are  based  on  entirely  different 

The  Scheiner  and  Din  speed  numbers  have  no  definite  relation  to  each 
other  nor  to  the  other  speed  values  except  for  emulsions  having  the  same 
characteristics  which,  however,  are  quite  different  for  the  various  kinds 
of  commercial  films  or  plates. 


Film  Selection 

Fig.  77     After  the  Catch 

Manuel  Komroff 

Hektor  50mm  lens,   1/100  second  at  f  :4.5.     DuPont  Superior  film 

To  give  a  rough  idea  of  the  relation  of  the  various  speed  values  a 
comparison  is  given  below  for  a  type  of  film  having  the  same  character- 
istic as  an  ordinary  commonly  used  film,  but  as  stated  above,  the  relative 
values  do  not  hold  for  other  types  of  emulsions  and  must,  therefore,  be 
used  with  due  caution. 

For  example,  a  report  of  an  actual  test  shows  that  26°  Scheiner  may 
be  equivalent  in  Din  degrees  to  any  value  from  12/10°  to  17/10°  Din, 
which  corresponds  to  a  ratio  of  over  3  to  1  in  sensitivity.  Further,  18/10° 
Din  may  "be  equivalent  in  some  emulsions  to  65  Weston  and  in  others  to 
24  Weston. 

Comparative  Table  of  speed  ratings  of  various  Systems. 

CAUTION — Do  not  use  this  table  without  reading  above. 





















































Following  are  suggestions  of  the  type  of  film  to  be  used  for  best 
results  in  different  kinds  of  work.  The  recommendations  refer  to 
groups  of  similar  emulsions  (see  above) ;  the  choice  of  any  one  film 
is  left  to  the  worker: 


of  Film 


Depending  on  light  conditions, 
density  and  color  of  filters  em- 
ployed    1  or  2 

In  daylight 3 

In  artificial  light 1 

Exteriors  alone  3  or  2 

Both  exteriors  and  interiors. ...     1  or  2 

Including  child  and  animal  pho- 
tography    1 

Blue-prints  (with  red  filter) 2 

Black  and  white  drawings, 
charts,  line  work,  documents  and 
other  printed  matter  in  black  and 
white  where  good  contrast  is  re- 
quired    4 

Coins,  stamps,  paintings,  fabrics 
or  any  other  small  or  large  ob- 
jects containing  color  or  requir- 
ing use  of  filters  for  better  con- 
trast    2 

Photographs  in  good  condition.     3 

Photographs,  old  or  faded  where 
use  of  red  filter  is  required 2 

Transparencies,  black  and  white, 
finger  prints,  X-rays,  etc 3 

Transparencies  containing  color    2 


Action  and  Sport 





Film  Selection 

Entomology  (insects  etc.)     1  or  2 

Flowers-Plants-Gardens        1  or  2 

Geology  (minerals)  2  or  3 

Landscape  and  Pictorial        If    true    color    correction    is    re- 
quired      1  or  2 

If   great    enlargements   and  fine 

grain    are    preferred 3 

Medical  For  general  use,  and  for  adverse 

light  conditions 1 

If  adequate  illumination  is  avail- 
able    2 

Dental  work 1 

Dermatology    3 

Ophthalmology    1 

Night  and  Stage  1 

Photomicrography  If  color  filters  are  required. ....  2 

If  no  color  filters  are  required. .  3 

For  living   organisms 1 

Portraiture                             If  adequate  illumination  is  avail- 
able      2 

For  adverse  light  conditions. ...  1 

General  Use  For  beginners   3 

If  outdoor  in  daylight 3  or  2 

If  entirely  or  partly  indoor,  or 
entirely  or  partly  under  artifi- 
cial light  2  or  1 

Natural  Color  5  A 

Infra-Red  5  B 

Reversal  Transparencies       5  C 

Daylight  Loading  and  Bulk  Film 

All  films  mentioned  here,  and  many  others,  are  available  in  two 

forms : 

1.  Daylight  loading  spools  or  cartridges  containing  from 
30  to  36  exposures. 

2.  Bulk  in  rolls  containing  25,  50,  100,  200  or  400  feet. 


The  daylight  loading  packings  are  lengths  of  film  from  5  to  6  feet,  cut 
and  trimmed  ready  for  loading  into  the  camera.  Some  packings  have  a 
paper  leader  strip  and  are  used  in  connection  with  the  regular  Leica  cam- 
era magazine.  Others  are  sold  in  the  form  of  ready-to-use  cartridge  maga- 
zines which  are  loaded  directly  into  the  camera.  For  convenience  and  ready 
availability  daylight  loading  packings  are  most  desirable. 

Bulk  film  has  many  advantages,  including  that  of  considerably  lower 
cost.  When  purchased  in  original  manufacturer's  packages  it  is  more 
likely  to  be  free  from  scratches  and  abrasion  marks  than  film  obtained  in 
daylight  loading  units.  Those  who  need  and  appreciate  uniformity  of  film 
will  find  that  bulk  film  offers  it,  since  a  roll  of  say  100  feet  is  the  same 
throughout,  and  once  its  characteristics  become  known  to  the  user,  they  can 
be  depended  upon  as  long  as  this  supply  is  used.  Bulk  film  also  offers  the 
advantage  that  it  can  be  cut  to  any  desired  length,  enough  for  forty  ex- 
posures or  perhaps  only  five.  It  is  recommended  to  buy  bulk  film  in  so- 
called  "automatic  camera"  packages  consisting  of  solid  metal  spools,  which 
provide  a  most  satisfactory  method  for  storing  and  handling  film,  protect- 
ing the  emulsion  and  edges  against  excessive  contact  with  fingers.  BULK 
should  not  be  attempted  by  workers  lacking  the  necessary  experience. 

Part  II  —  Film  Exposure 

The  last  decade  has  witnessed  an  interesting  trend  in  the  field 
of  photography.  Both  the  professional  and  amateur  workers  had 
gradually  become  exposure  conscious.  They  began  to  realize  that 
every  important  characteristic  of  the  finished  photograph  takes  its 
root  at  the  time  the  exposure  is  made,  and  that  the  desired  result  de- 
pends upon  their  ability  to  coordinate  judicious  exposure  with  skilful 
development  of  the  negative. 

The  Leiea  camera  is  in  a  great  measure  responsible  for  this 
realization.  Leica  photography  has  established  a  definite  system  based 
on  the  successful  application  of  a  number  of  principles.  One  of  these 
principles  is  a  certain  uniformity  of  exposures,  since  as  many  as 
thirty-six  negatives  are  usually  developed  at  the  same  time,  and  in- 
dividual negatives  cannot  be  controlled  in  the  development. 

This  requirement  of  Leica  photography  brought  about  the  in- 
terest in  normal  exposure.  Normal  exposure  is  that  which  places 
the  range  of  brightness  somewhere  in  the  middle  of  the  limits  of  the 
latitude  of  the  emulsion.  In  terms  of  ,§yery  day  work  normal  ex- 
posure strikes  a  compromise  between  tfie  light  and  dark  portions  of 
the  subject  so  that  the  bright  portions  are  not  overexposed  while 

details    in    "f"^01    QlnarlA^xrc!     QT»/S     T»onr»T»rl  n/--!     -f/-v/-v 


Film  Exposure 

Prom  this  point,  within  the  limits  of  the  latitude  of  a  given 
emulsion,  a  range  of  exposures  favoring  either  the  shadow  details 
or  the  highlights  is  available,  depending  upon  whether  the  pre- 
dominant part  of  the  photograph  is  to  bring  out  the  dark  or  light 
portion  of  the  subject.  Which  brings  us  to  the  matter  of  correct 
exposure.  That  exposure  is  correct  which  puts  on  film  exactly  what 
is  wanted  in  the  picture. 

A  great  variety  of  exposure  meters  and  tables  is  available  to 
assist  us  in  obtaining  normal  exposures.  But  correct  exposures  do 
not  necessarily  mean  normal  exposures.  While  normal  exposures 
are  within  reach  of  every  owner  of  a  reliable  exposure  meter,  cor- 
rect exposures  require  judgment  and  skill  on  the  part  of  the  pho- 
tographer— the  knowledge  of  when  and  how  to  use  over  or  under- 
exposure to  get  what  is  wanted  in  the  picture.  This  knowledge 
comes  with  practice  and  experience. 

Exposure  Meters 

Exposure  meters  are  essentially  of  three  types: 

1.  Exposure  tables  and  calculators  are  helpful  guides  to  normal  exposures 
based  on  compiled  actual  experiences.     Some  of  these  are  available  in 
the  form  of  direct  tables  which  suggest  approximately  normal  exposures 
for  different  emulsions  and  for  various  subjects,  taking  into  consideration 
time  of  day,  location,  season,  weather,  etc.     Others  are  put  up  in  the 
form  of  slides  or  discs  made  of  cardboard,  celluloid,  etc.    Then  there  are 
some  in  the  form  of  booklets  containing  in  addition  to  suggestions  con- 
cerning exposures  a  variety  of  information,  references,  etc.     The  chief 
merit  of  all  of  these  lies  in  their  providing  some  basis  for  arriving  at  a 
more  or  less  normal  exposure. 

2.  Visual  exposure  meters  which  are  frequently  known  as  the  "extinction 
type"  require  sighting  the  subject  through  a  ground   or  tinted  glass 
screen  while  the  amount  of  light  admitted  is  gradually  reduced  to   a 
minimum.    When  that  minimum  is  reached  a  scale  indicates  the  desired 
data.     The  greatest  disadvantage  of  this  type  of  meter  is  the  impossi- 
bility to  assume  a  standard  sensitivity  of  the  eye  to  light.     Its  chief 
advantage  is  its  ability  to  give  readings  in  extremely  unfavorable  light 
conditions  of  interiors  and  night  photography.    Any  one  of  these  instru- 
ments, if  used  consistently  and  with  judgment,  will  provide  usable  in- 
formation as  to  normal  exposure. 

3.  Photometric  exposure  meters  are  the  latest  and  to  date  most  accurate 
and   dependable  means  for  ascertaining  normal   exposures.     They  are 
usually  made  as  instruments  of  great  accuracy  and  precision,  and  should 
be  handled  as  such.     The  instruments  are  built  around  a  photoelectric 
cell  which  converts  light  energy  into   electrical  energy,  which  in  turn 
activates  extremely  sensitive  miliammeters  calibrated  in  terms  of  light 
values.     Such  popular  photoelectric  instruments  as  the  Weston  or  the 
Photoscope,  though  comparatively  expensive,   belong  actually  to  those 
self-liquidating  investments   which   earn  their  price  through   constant 
economies  of  film,  elimination  of  uncertainty  and  securing  results. " 


Fig.  78     Weston  Photoelectric 
Leicameter,  New  Model  No.  650 

Any  of  these  exposure  meters  when  used  strictly  in  accordance  with 
manufacturer's  instructions  will  yield  results  of  surprising  accuracy.  Each 
has  its  own  advantages  and  a  careful  comparison  of  them  should  be  made 
before  deciding  which  one  will  answer  individual  requirements.  It  is  difficult 
to  make  specific  recommendations  because  of  the  vastness  of  the  field  which 
Leica  photography  covers  today. 

There  are  no  factotums  in  photography.  The  more  one  knows  about 
photography  the  more  difficult  it  becomes  to  point  specifically  to  any  one 
film,  exposure  meter,  lens,  developer,  paper  and  attach  the  term  "universal" 
to  it.  Only  a  careful  examination  of  the  product  and  scrutiny  from  the 
viewpoint  of  what  it  is  expected  to  perform  will  determine  its  usefulness. 

No  matter  what  the  relative  merit  of  any  of  these  meters  may  be,  it 
is  safe  to  state  that  the  consistent  use  of  any  one  of  them  will  yield  results 
far  superior  to  those  obtained  by  guesswork. 

How  to  Use  an  Exposure  Meter 

An  exposure  meter,  very  much  like  a  lens,  has  a  very  definite 
field  coverage,  varying  with  the  make.  The  manufacturer  supplies 
this  information  with  every  instrument.  The  area  covered  should  be 
thought  of  as  the  base  of  a  cone  whose  apex  is  in  the  center  of  its  light 
sensitive  surface.  The  angle  of  this  apex  varies  anywhere  from  50° 
to  70°. 

It  should  be  remembered  that  a  meter  has  no  power  of  selectivity. 
For  instance,  if  a  reading  is  taken  of  a  dark  object  back  of  which 
is  a  light  surface,  the  meter  will  give  a  reading  proportionate  to  the 
relative  amount  of  light  and  dark  portions  of  the  entire  area  which 
it  "sees".  One  should  endeavor,  therefore,  to  take  a  reading  by 
holding  the  meter  as  close  as  possible  to  the  object  for  whose  detail 
the  exposure  is  to  be  made.  The  meter  should  be  held  in  a  manner 
to  prevent  its  shadow  being  cast  on  the  area  under  observation. 


Film  Exposure 

When  taking  the  reading  of  small  objects  occupying  only  a  small 
portion  of  their  background,  the  proper  way  to  secure  a  correct  read- 
ing is  by  the  method  of  substitution.  A  sheet  of  paper  or  fabric  of 
a  color  and  brightness  approximating  that  of  the  small  object  should 
be  placed  over  the  object  and  its  background  and  a  reading  secured 
from  that.  For  instance,  if  teeth  are  photographed  and  the  meter 
directed  on  the  face  or  mouth,  considerable  overexposure  of  the  teeth 
would  result,  because  the  skin  and  lips  are  darker  than  the  teeth. 
However,  if  a  piece  of  ivory  tinted  paper  is  placed  over  the  face  and 
the  meter  directed  on  that,  a  correct-exposure  of  the  teeth  will  result, 
while  the  lips  and  skin  will  be  somewhat  underexposed.  This  example 
is  quoted  merely  in  the  hope  that  it  will  assist  in  the  judicious  use 
of  exposure  meters.  Here  again,  the  purpose  of  the  picture  must  be 
borne  in  mind. 

Needless  to  say,  instructions  accompanying  every  instrument 
should  be  read  and  followed  carefully. 

Pig.  80     Doug 

Barbara  Morgan 
Summar     50mm     lens, 
1/100   second   at   f:6.3 
DuPont    Superior   film 

How  to  Make  Exposures  Without  an  Exposure  Meter 

If  an  exposure  meter  is  not  readily  available,  or  if  there  be  no  time  to 
use  one,  the  following  method  is  recommended: 
Set  your  shutter  speed  at  1/30  or  1/40  of  a  second. 

If  the  sun  is  shining  unobstructed  by  clouds,  make  three  exposures  of  the 
subject:  one  with  the  lens  set  at  f  :6.3,  one  at  f  :9,  and  one  at  f  :12.5, 
If  the  sun  is  obstructed  by  clouds  (no  shadows  cast),  take  three  exposures 
of  the  subject:  one  with  the  lens  at  f  :6.3,  one  at  f  :4.5,  and  one  at  f  :3.5  (or 
larger  opening1  if  available). 

This  rule-of -thumb  method  seldom  fails  to  produce  at  least  one  usable 
negative  out  of  three  taken.  When  in  extreme  doubt  make  a  fourth  exposure 
either  at  a  larger  or  smaller  opening  than  indicated  above.  Remember  your 
film  is  the  least  expensive  part  of  your  equipment  while  opportunities  for 
pictures  rarely  repeat  themselves. 


Exposures  for  Photoflash 

Average   Distance    Covered    by    One    General    Electric    Mazda    Photoflash 

Lamp    in    a   Eeflector 

Approx.  Distance  of  Lamp  to'Subject 
Ortho  Film  Super-sensitive  Pan 
Group  No.  3  Group  No.  1  Film 

5  ft.  7  ft. 

7  10 








Size  of 
No.  10 
No.  20 

No.  10 
No.  20 

No.  10 
No.  20 

No.  10 

No.  20 

No.  10 
No.  20 











These  figures  are  based  on  a  room  with  medium  colored  walls  and 
ceiling.  Where  pictures  are  made  outdoors  or  under  adverse  conditions 
at  the  greater  distances,  use  the  next  larger  diaphragm  opening  or  reduce 
distance  from  lamp  to  subject  to  about  70  per  cent  of  that  shown. 

Part  III  —  Film  Development 

Development  with  Relation  to  Exposure 

Leiea  negatives  will  produce  excellent  enlargements  if  they  meet 
two  requirements : 

1.  Fineness  of  grain. 

2.  A  comparatively  low  degree  of  contrast. 

Both  of  these  conditions  can  be  met  by  carefully  selecting  the 
negative  material  and  by  coordinating  the  exposure  with  the  de- 

Leica  negatives  must  be  processed  with  low  energy  developers 
which  act  gently  and  slowly.  Development  is  carried  out  on  the 
time-and-temperature  principle. 

Most  fine  grain  developers  adopted  for  Leica  work  are  carefully 
and  scientifically  compounded  to  act  uniformly  and  to  produce  pre- 
determined results.  It  is  not  necessary  to  delve  into  details  of  sensi- 
tometry  to  obtain  such  predetermined  results.  To  provide  a  means 


Film  Development 

of  comparison  of  densities  and  contrasts,  scientists  have  evolved  a 
definite  system.  The  unit  in  which  the  functional  dependence  of 
density,  contrast  and  exposure  is  expressed  is  the  term  gamma  (y) 
which  is  defined  as  a  numerical  expression  for  the  contrast  of  the 
negative  obtained  from  a  range  of  given  exposures  carried  out  in  a 
given  developer  in  a  given  time. 

Depending  upon  the  size  of  the  finished  enlargement,  the  gamma 
of  Leica  negatives  should  vary  between  .6  to  .8.  The  lower  value, 
which  stands  for  lo\ver  density  and  contrast,  should  be  aimed  at  for 
greater  enlargements;  while  the  higher  value  for  smaller  enlarge- 
ments. Gamma  of  approximately  .7  will  be  found  excellent  for  all- 
around  purposes,  and  it  is  the  gamma  value  of  .7  on  which  the 
time-and-temperature  units  should  be  based  for  the  various  fine 
grain  developers. 

Density  and  contrast  of  a  negative  corresponding  to  gamma  value 
.7  are  based  upon  normal  exposure.  Consequently,  underexposures 
with  the  same  development  will  result  in  higher  contrast  and  less 
detail  in  the  shadows;  while  over  exposure  under  the  same  developing 
conditions  will  result  in  lower  contrast  and  more  detail  in  the 

The  time-and-temperature  factors  for  a  given  developer  to 
produce  gamma  .7  stand  for  minimum  development.  This  minimum 
is  necessary  to  assure  fineness  of  grain  and  low  contrast.  If  de- 
velopment is  carried  beyond  that  minimum,  it  is  likely  to  increase 
both  graininess  and  contrast.  In  order  that  development  be  held 
to  this  minimum  and  still  bring  out  as  much  detail  in  the  negative 
as  possible  LEICA  NEGATIVES  MUST  BE  FULLY  EXPOSED.  Briefly: 
OVEREXPOSE — UNDERDEVELOP  !  .  .  .  within  reason  of  course.  To  put 
this  in  terms  of  practical  application,  the  film  speed  ratings  usually 
published  should  be  considered  as  somewhat  over-rated,  and  for  best 
results  the  films  should  be  used  at  ratings  slightly  below  the  ' '  official ' ? 

Developing  Equipment 

The  equipment  for  developing  Leica  film  is  extremely  simple,  easy 
to  handle  and  with  proper  care  will  last  a  lifetime. 

For  convenient  development  of  Leiea  film  there  are  two  tanks,  the 
Correx  and  the  Reelo.  There  is  also  a  glass  developing  drum.  Instruc- 
tions for  handling  accompany  each  one.  The  tanks  should  be  used  pre- 
ferably in  all  cases,  except  for  reversal  where  the  developing  drum  alone 
or  in  connection  with  one  of  these  tanks  is  recommended.  The  greatest 
advantage  of  developing  Leica  films  in  one  of  these  tanks  is  the  fact  that 
no  dark  room  is  needed  for  the  process.  Once  the  film  is  transferred  into 
the  tank  (this  can  be  accomplished  in  a  changing  bag),  the  development 
and  subsequent  handling  do  not  require  darkness. 


Fig.  81     The  Reelo— All  Bakelite  Developing  Tank 

These  two  tanks  differ  from  one  another  by  the  method  in  which  sepa- 
ration of  the  film  layers  is  accomplished.  In  the  Correx  tank  the  film  is 
separated  by  means  of  a  celluloid  apron  with  studded  edges,  while  in  the 
Reelo  tank  it  is  separated  by  the  grooved  spool.  The  tanks  are  equally 
effective  and  selection  between  them  is  a  matter  of  personal  preference. 

The  capacity  of  the  Correx  tank  is  about  500.0  cc,  or  16  ounces;  and 
that  of  the  Reelo  about  400.0  cc,  or  12  ounces. 

Fig.  82     Glass  Developing 
Drum  and  Tray 

Fig.  83  The  Correx 
—All  Bakelite  De- 
veloping Tank  with 
celluloid  Studded 
edge  Apron  and 


FUm  Development 

Fig.  84     Method  of  Winding  Film  upon 
Reelo  Spool. 


Those  who  wish  to  process  their  films  themselves  may  use  any  one  of 
the  prepared  ready-to-use  developers  on  the  market,  which  are  available 
either  in  powder  form  or  in  concentrated  liquid  form.  These  preparations 
will  give  excellent  results  if  used  strictly  in  accordance  with  manufacturer's 



A  more  economical  and  possibly  more  practical  way  to  produce 
excellent  negatives  is  to, prepare  one's  own  developer  as  well  as  other 
solntions  required  for  processing  Leica  negatives.  A  few  simple 
chemicals,  a  scale  and  a  few  graduates,  are  all  that  is  necessary. 

The  number  of  formulas  offered  for  fine  grain  development  is 
enormous.  A  careful  study  of  them  reveals  the  important  fact  that 
in  addition  to  some  processes  which  have  purely  experimental  merits, 
there  are  only  two  classical  basic  formulas  available.  Others  are 
merely  modifications  of  these  two: 

1.  The  Metol  Hydroquinone  Borax  type. 

2.  The  Paraphenylene  Diamine  type. 

The  first  type  represents  a  developer  which,  as  far  as  miniature 
camera  work  goes,  can  be  termed  the  maximum  energy  developer. 
It  will  bring  out  details  in  shadows  and  underexposed  portions  of 
the  negative  to  a  remarkable  degree,  while  it  will  produce  granu- 
larity of  sufficient  fineness  to  yield  excellent  enlargements  up  to 

The  second  type  is  a  low  energy,  extremely  fine  grain  developer 
which  requires  a  fuller  exposure  than  the  first  type,  but  in  return  will 
yield  negatives  of  such  fine  grain,  excellent  definition,  and  low  con- 
trast that  enlargements  of  16x20"  can  easily  be  obtained. 

Reference  to  fine  grain  performance  of  these  two  developers  is  made 
specifically  in  connection  with  films  of  Group  1,  which  due  to  their  speed 
have  an  inherently  coarser  grain  structure. 


events  with  the  Leica — Barbara  Morgan  designed  a  series  of  fifteen  different  montages  of 
various  school  activities.  This  is  an  example  of  paste  up  montage — the  simplest  "type  using 
many  individual  pictures. 

Developing  Formulas 

The  Metol-Hydroquinone  -Borax  type  of  fine  grain  developer  is 
represented  by  the  classical  formula  known  as  Eastman  Kodak  D-76, 
or  its  derivative  the  Modified  E.K.D-76,  also  known  as  Buffered 

E.K.  Formula  D-76 

Avoirdupois  Metric 

Water  (about  125°F.  or  52°C.) 24          ounces  750.0  cc 

Metol 29          grains  2.0  grams 

Sodium  Sulphite,  desiccated  3  1/3  ounces  100.0  grams 

Hydroquinone 73          grains  5.0  grams 

Borax  (the  20-Mule  Team  variety) 29          grains  2.0  grams 

Cold  water  to  make   32         ounces  1.0  liter 

Dissolve  the  chemicals  in  the  order  given. 

Use  without  dilution. 

Develop  16  to  22  minutes  at  65 °F.  or  18  °C.  for  films  of  Group  1   or  3. 

Develop  12  to  18  minutes  at  65  *F.  or  18  °C.  for  films  of  Group  2. 

This  formula  can  be  re-used  and  the  quantity  is  sufficient  to  develop  from  8  to  10  Leica  film 


Modified  E.K.  Formula  D-76  (Buffered  Borax  Negative  Developer) 

Avoirdupois  Metric 

Water  (about  125°F.  or  52°C.) 24          ounces  750.0  cc 

Metol 29          grains  2.0  grams 

Sodium  Sulphite,  desiccated   3  1/3  ounces  100.0  grams 

Hydroquinone 73          grains  5.0  grams 

Borax  (the  20-Mule  Team  variety) . . 29          grains  2.0  grams 

Boric  Acid,  crystals  203          grains  14.0  grams 

Cold  water  to  make   32         ounces  1.0  liter 

Dissolve  the  chemicals  in  the  order  given. 

Use  without  dilution. 

Develop  20  to  22  minutes  at  65  °F.  or  18  °C.  for  films  of  Group  1  or  3. 

Develop  16  to  18  minutes  at  66  °F.  or  18  °C.  for  films  of  Group  2. 

This  formula  can  be  re-used  and  the  quantity  is  sufficient  to  develop  from  8  to  10  Leica  film 


The  two  developers  given  above  should  be  used  for  films  of  Group  1  in 
all  cases  where  it  is  known  that  the  film  has  received  the  minimum  possible 
exposure  due  to  adverse  light  conditions    (such  as  encountered  in  stage, 
night,  candid  and  actions  photography). 
They  are  excellent  standard  developers  for  all  films  of  Group  2  and  3. 

The  Paraphenylene  Diamine  type  of  fine  grain  developer  is  em- 
bodied in  a  comprehensive  set  of  four  formulas  designed  by  Dr.  Sease 
of  the  DuPont  Film  Laboratories.  These  four  formulas  are  remark- 
able for  their  delicately  balanced  -proportions  of  the  same  three  in- 
gredients: Sodium  Sulphite,  Paraphenylene  Diamine  and  Glycin, 
with  the  latter  gradually  increasing : 


JrlLm  Development 


E^    3      2 

5  u 


_  5  S 

o    o    o 
o    eJ    N 



^P                    10 

0»     r-4     TH 




tfl      W 


Tf    1C    O 

g               CO  C^   OO 

o  en  CM 

I>>  <y5  rH 


*      * 

.s  .s 


T-H   rH 


rH  rH  rH 

.    "eS     «S 

"S      N 

N      >M      5-i 

>      0 

0      bfl     t» 

•<  ^ 

CO     «o     »O 



•5*    t> 











rt  -     -              « 


*s  ° 

fci          <i> 



•+•»     ^ 






53  ^ 

A*    ^  <=> 
CO         10 


O  0  O          *£Q 

C>  O  CO 








^           CM  cn>  -HH 

-*j               CO  CS*  CO 

•HK   CS   rH 
CO  00  0 

Tt*   CM  Oi 
CF5    CO   Td* 


2  2  a> 

SH    S  ^»    d) 



g                       rH  rH 


rH   tH 



.  "ctf  "cS  ^  T^J 




"o  § 

N     Vi     ^           "^ 
p    &JD   bCrH    pj 







CO  CO  00     fH  "'~l 
•*^   OO     O     02 


^             W^ 








s  s 



S                  PS    0> 




"S     « 

a;  5  ^ 




5    ° 

C3     0     0  CO    £3 
0      0     T-H                03 





^^              10 



g  CM   t-  rH 
.S  <Mi  ^  'r~{ 

OJ               <Ji  O  OO 

m           -^  oo  05 

0  O  O5 

to  t-  t- 

•<e#   t-»   CM 
OO  rH  CO 

«     w          'o 



,-<  ^ 

*O        N 

*2    "S           W 

N  2   2      ™ 



>        0 

e     611    M        g 





^      TH 















cd    2 



*a        W 





«    o 

S       o 

o    ^ 
o    o 




crs    r-« 


2  CM  ^1   "^H 

^                fH  |>.  CM 

^  CM  O 

CM  CM  -r^ 



.g   CO  ^   rH 

03               r^  CO  00 

Tt<  co  t* 

t»  O  rH 








rH  TH 



521  1  i 

g   1 

CO     CO 










g  . 

0         * 




-H   OO  CM 
iH   CM  ^ 

•H4  00  CM 
rH  CM   «tf 





CO       - 

§        g 


II   1 


°  P5  <^ 

rH  >»    ft 





il  1 

S    5S    O 

2  2o 

«_.                               /"N 

e              °° 


"3  *>>      *^ 










3  s>  s  2 

5   p*i  "   o 


1  §«" 

03      .S    A   A 

O     JES  **   s 


S    !3  CiJ 
H  02  w- 

(Group  2 







Formula  number  3  should  be  considered  standard. 

Formula  No.  1,  which  yields  the  finest  possible  grain,  requires  from 
three  to  four  times  the  normal  exposure  for  the  Superior  (Group  1  or  3) 
film  or  the  Infra  D  (Group  5B)  emulsion  but  requires  little  or  no  increase 
of  exposure  for  the  Micropan  (Group  2)  film. 

Formulas  No.  2,  3  and  4,  which  yield  very  fine  grain  (the  finer  the 
less  Glycin  the  formula  contains),  require  about  two  times  the  normal 
exposure  for  the  Superior  (Group  1  or  3)  film  or  the  Infra  D  (Group  5B) 
film,  but  require  little  or  no  increase  with  Micropan  (Group  2). 

These  requirements  for  overexposure  should  be  considered  as  merely 
approximate  and  as  referring  actually  to  minimum  exposures  when  these 
films  are  used  under  inadequate  light  conditions.  One  may  interpret  the 
latent  image  formed  on  the  emulsion  as  having  a  certain  amount  of  in- 
ertia which  is  greater  the  lower  the  energy  of  the  developer.  Thus  the 
greater  the  so-called  threshold  value  of  the  light  that  strikes  the  emulsion, 
the  easier  it  is  for  these  low  energy  developers  to  "pull  up"  the  image. 
Consequently  when  exposures  are  made  in  full  brilliant  light,  the  require- 
ments for  overexposure  stated  above  are  not  as  great  as  those  under 
adverse  light  conditions. 

Compromise  Developers 

Neither  of  the  two  types  of  developer  described  above  is  entirely 
satisfactory  for  certain  kinds  of  work  where  photographs  taken  under 
extremely  poor  light  conditions  must  be  considerably  enlarged.  Such 
a  situation  is  frequently  encountered  in  stage,  action  and  candid 
photography.  For  such  purposes  ' £  compromise ? '  formulas  were 
evolved  which  produce  excellent  shadow  detail,  gradation  and  con- 
trast, combined  with  exceptionally  fine  grain — in  cases  where  only 
minimum  exposures  were  possible. 

Two  such  formulas  are  offered,  either  of  which  is  a  modification 
of  Dr.  Sease  No.  3  formula : 

Pyro  Fine  Grain  Formula  for  Not  Fully  Exposed  Negatives 

Avoirdupois  Metric 

Water  (about  135°  F.  or  57°  C.).  •     24      ounces  750.0  cc 

Sodium  Sulphite,  desiccated 3      ounces  90.0  grams 

Paraphenylene  Diamine   146.     grains  10.0  grams 

Boric   Acid   14^  grains  1,0  gram 

Cold  water  to  make    32      ounces  1,0  liter 

Dissolve  chemicals  in  the  order  given. 

Directly  before  "using  add  to  every  SGOcc  (16  ounces)  of  the  above  solution; 

Pyro    Crystals    43J/2  grains  3.0  grams, 

filter  and  cool  to  65°  F.  or  18°  C. 

Develop  30  minutes  for  films  of  Group  ]    or  3. 

This  developer  cannot  be  re-used  after  addition  of  Pyro. 

Store  it  without  Pyro. 

The  other  compromise  formula  is  based  on  the  well  known  property  of 
Metol  to  bring  out  shadow  detail  and  gradation. 


Film  Development 

Metol  Fine  Grain  Formula  for  Not  Fully  Exposed  Negatives 

Avoirdupois  Metric 

Water  (about  125°  F.  or  50°  C.)  .  . .  24  ounces  750.0  cc 

Paraphenylene  Diamine 146  grains  10.0  grams 

Glycin     73  grains  5.0*  grams 

Metol 88  grains  6.0  grams 

Sodium   Sulphite    3  ounces  90.0  grams 

Cold  water  to   make 32  ounces  1.0  liter 

Dissolve  chemicals  in  the  order"  given. 

Use  without  dilution. 

Develop  18  minutes  at  65°  F.  or  18°  C.  for  films  of  Group  1  or  3. 

Develop  12  minutes  at  65°  F.  or  18°  C.  for  films  of  Group  2. 

This  formula  can  be  re-used  and  the  quantity  is  sufficient  to  develop  from  8  to  10  Leica 

film  lengths.     It  definitely  improves  with  age  and  use. 

The  developers  described  cover  practically  the  entire  range  of 
Leica  photography,  and  although  there  are  hundreds  of  fine  grain 
formulas  offered  almost  every  day,  as  matters  stand  now  these  should 
be  considered  best  suited  to  successful  Leica  photography.  These 
developers  were  chosen  because  of  their  simplicity,  limited  number  of 
ingredients,  for  their  comparatively  rapid  action  and  for  their  de- 
pendability. If  used  strictly  in  accordance  with  instructions  they 
can  be  depended  upon  for  consistently  uniform  negatives. 

Although  the  following  statement  holds  true  of  almost  every 
phase  of  photographic  procedure,  it  is  of  particularly  great  impor- 
tance in  connection  with  the  preparation  and  use  of  developers :  A 
person  not  following  a  recommended  procedure  is,  at  present,  enter- 
ing* a  field  of  research  where  definite  results  cannot  be  promised. 

Conservative  use  of  developers  which  can  be  re-used  permits  the 
development  of  8  to  10  Leica  rolls  per  100(XOcc  (32  ounces)  of  de- 
veloper with  an  increase  of  one  minute  developing  time  per  roll 
processed,  i.e.,  one  minute  increase  for  the  second  roll,  two  minutes 
for  the  third  roll,  etc. 

Any  one  of  the  above  formulas  (except  the  Pyro  "compromise" 
formula)  can  be  re-used  within  reasonable  standing  periods,  but  exact 
figures  as  to  their  keeping  qualities  would  be  of  little  direct  value  because 
conditions  of  use  and  storage  differ  widely. 

Between  developments  the  solutions  should  be  stored  in  nearly  full 
well-stoppered  amber  glass  bottles  with  a  special  label  provided  for  mark- 
ing the  developer  every  time  it  is  used.  The  developer  should  be  poured 
back  into  the  original  bottle  after  each  use,  until  it  has  been  used  on  8  to 
10  rolls,  after  which  it  should  be  discarded  or  set  aside  for  "priming"  the 
next  batch  of  developer. 

'  It  is  worth  noting"  that  most  fine  grain  developers  produce  finer  grain 
and  lower  contrast  the  older  they  are  or  the  more  they  have  been  used. 
Most  freshly  prepared  developers  work  more  energetically  than  those  some- 
what ag-ed  and  used.  The  fresh  solutions  have  that  "fire"  in  them;  and 
for  those  who  wish  slightly  softer  results  and  finer  grain  it  is  recom- 
mended that  they  "prime"  the  developer  either  by  adding  some  25%  of 


the  same  developer  ready  to  be  discarded,  or  by  developing  in  the  fresh 
developer  a  length  of  say  5  to  6  feet  of  fogged  film.  This  produces  a 
certain  amount  of  oxidation  in  the  developer  which  takes  the  "fire"  out 
of  it  and  softens  its  action. 

Temperature  of  Developers 

Suggestions  given  in  every  developer  formula  for  a  temperature 
at  which,  the  development  is  to  be  carried  out  should  be  followed 
strictly.  At  temperatures  below  those  indicated  the  developing  agents 
may  be  partly  or  completely  inactive;  while  at  temperatures  higher 
than  those  indicated  the  rate  of  development  may  be  accelerated  with 
resulting  increase  in  graininess,  density  and  contrast. 


As  a  general  rule  continuous  and  vigorous  agitation  is  definitely 
to  be  avoided  when  developing  for  finest  grain.  Continuous  agitation 
increases  the  rate  of  development,  which  actually  should  be  compen- 
sated for  by  shortening  the  time.  However,  this  would  require  a 
careful  study  of  systematically  developed  test  strips  to  insure  uni- 
formity of  results,  which  would  depend  upon  the  type  of  agitator, 
its  speed,  direction,  etc. 

Occasional  gentle  agitation  every  three  to  five  minutes,  however, 
is  not  only  recommended  but  urged.  Such  agitation  does  not  increase 
the  rate  of  development  nor  affect  the  time  indicated,  and  is  required 
to  prevent  streaking  along  the  perforations  of  the  film. 

The  Short-stop  and  the  Fixing  Bath 

Before  proceeding  with  the  details  of  actual  development,  one  should 
be  familiar  with  the  only  other  two  solutions  required  for  complete  pro- 
cessing of  Leica  films: 

The  Intermediary  Short-stop  and  Hardening  Bath.  The  following  solu- 
tion seems  to  have  many  features  which  should  make  it  indispensable  in  the 
processing  of  Leica  films: 

Intermediary  Short-stop  and  Hardener 

Avoirdupois  Metric 

Water    16  ounces          500.0  cc 

Chrome    Alum    145  grains  10.0  grams 

Sodium  Bisulphite    145  grains  10.0  grams 

Dissolve   Chrome   Alum    completely   before    adding    Sodium    Bisulphite ; 

stir  until   Sodium  Bisulphite  is  completely  dissolved. 

Use  without  dilution. 

This  solution  should  be  used  at  the  same  temperature  as  that  of  the 


Film  should  be  left  in  this  bath  for  five  minutes. 

This  solution  should  be  prepared  just  before  required  and  discarded 

once  used. 

Actual  use  of  this  short-stop  on  hundreds  of  rolls  of  Leica  films  proved 
its  value.  It  gently  checks  development  and  gradually  hardens  the  emul- 
sion, the  hardening  process  being  continued  in  the  acid  fixing  bath  which 
follows.  This  intermediate  bath  seems  to  correct  the  acidity  of  the  subse- 


Film  Development 

quent  acid  fixing  bath,  to  a  degree  which  eliminates  the  danger  of  reticula- 
tion at  that  point. 

The  hardening  properties  of  this  intermediate  bath  are  such  that 
negatives  treated  in  it  are  almost  impervious  to  scratches.  It  accelerates 
final  drying  of  the  film  by  contracting  the  layer  of  gelatine  to  its  mini- 
mum, thus  expelling  as  much  moisture  as  possible.  The  emulsion  of  a 
negative  treated  in  this  solution  and  the  subsequent  acid  fixing  bath  shows 
a  remarkably  glazed  surface  which  makes  it  almost  difficult  to  distinguish 
the  emulsion  side  from  the  back  of  the  film.  This  glaze  is  proof  not  only 
of  sufficient  hardness  of  the  emulsion  and  fineness  of  grain,  but  also  of  the 
absence  of  reticulation. 

The  Acid  Hardening  Fixing  Bath.     This  is  the  final  solution  required 
for  processing  Leica  films  and  its  purpose  is  to  dissolve  the  unexposed 
portions  of  the   silver  and  thus   render   it  insensitive  to   light.     Another 
^  function,  of,  .this  fixing  bath  is  to  harden  the  emulsion. 

While  the  packaged  form  of  acid  fixing  powders  which  merely  requires 
solution  in  a  given  quantity  of  water  is  quite  satisfactory,  far  superior  and 
consistently  satisfactory  results  are  obtained  by  the  use  of  the  newest 
formula  offered  by  Eastman  Kodak  Company: 

Acid  Hardening  Fixing  Bath  far  Films 
Formula  E.K.  F-5 

Avoirdupois  Metric 

Water  (at  about  125°  F.  or  52°  C.)  . . .   20      ounces  600.0  cc 

Hypo  (pea  crystals  or  rice  crystals) . .     8      ounces  240.0  grams 

Sodium   Sulphite,    desiccated y2  ounce  15.0  grams 

*  Acetic  Acid,  28%    pure.... l!/2fl.  ounces  47.0  cc 

Boric   Acid,   crystals    l/4  ounce  7.5  grams 

Potassium    Alum    y2  ounce  15.0  grams 

Cold  water  to  make   32      ounces  1.0  liter 

*To  make  28%  acetic  acid  from  glacial  acetic  acid,  dilute  3  parts  of  glacial  acetic  acid 
with  8   parts  of  water. 
Directions  for  mixing: 

Dissolve   the   Hypo   in   about   one-half   the    required    volume   of   water ;   then    add   the 
remaining  chemicals  in   the   order  given,  taking   care  that  each   chemical  is   dissolved 
before  the  next  is  added.    Then  dilute  with  water  to  the  required  volume. 
The  film  should   be   left  in   this   hypo   bath   for    10    minutes    (temperature   should  be 

-  preferably  'the  same  as  that  of  the  developer) ,  and  it  is  frankly  recommended  to  use 
the  hypo  for  fixing  of  film  once  only,  after  which  it  may  be  collected  in  a  separate 
bottle  for  fixing  of  paper.     This  may  be  considered  by  some  as  somewhat   extrava- 
gant,  but  it  should  be  worth  while  to   know  that  this   final   step  in  processing  some 
thirty  negatives   will   insure  their  longevity,  -which   greatly   depends   on  the  freshness 
and  strength  of  the  hypo. 

For  those  who  require  larger  quantities  of  acid  fixing  bath  it  is  rec- 
ommended that  they  keep  a  separate  solution  of  straight  Hypo  and  a 
separate  Acid  Hardener  Stock  Solution,  mixing  them  in  proper  proportions 
just  before  using.  This  results  in  fresher  solution  when  required: 

Acid  Hardener  Stock  Solution 
Formula  E.K.  F-5a 

Avoirdupois  Metric 

Water  (at  about  125°  F.  or  52°  C.)...   20      ounces  600.0  cc 

Sodium  Sulphite,  desiccated 2^  ounces  75.0  grams 

Acetic  Acid,  28%    pure    ll/2  fl.  ounces  235.0  cc 

Boric  Acid,  crystals   1  *4  ounces  37.5  grams 

Potassium  Alum 2*/2  ounces  75.0  grams 

Cold  water  to  make   32      ounces  1.0  liter 

Dissolve   chemicals  in  the   order  given,    taking   care   that   each   chemical   is   dissolved 

before  the  next  is  added. 

Add  slowly  one  part  of  the  cool  Acid  Hardener  Stock  Solution  to  four  parts  of  cool 

30%  hypo  solution  (2^  pounds  of  hypo  per  gallon  of  water)  while  stirring  the  latter 



Washing  the  Film 

After  fixing,  the  film  should  be  thoroughly  washed  to  remove  all  traces 
of  Hypo,  otherwise  the  negatives  may  in  time  develop  stains.  Washing  is 
best  carried  out  while  the  film  is  still  in  the  developing  tank.  A  steady 
stream  of  water,  not  colder  than  65°  F.  (18°  C.)  nor  warmer  than  70°  F. 
(21°  C.),  should  be  permitted  to  run  into  the  tank  through  the  opening  in  its 
cover  for  not  less  than  20,  preferably  for  30  minutes.  If  it  be  important 
to  wash  the  film  quickly,  it  is  suggested  to  proceed  as  follows:  Fill  the 
tank  with  water,  agitate  it  for  one-half  to  one  minute,  pour  the  water  out. 
Repeat  this  operation  six  or  seven  times.  The  film  ought  to  be  free  from 
Hypo  at  the  end  of  this  procedure,  and  ready  for  drying. 

Drying  the  Film 

The  film  should  be  carefully  removed  from  the  developing  reel  and 
hung  from  one  end  by  means  of  a  clip.  It  is  best  to  suspend  the  film  so 
that  it  will  not  come  in  contact  with  the  wall  or  other  objects  while  drying. 
With  a  Viscose  Sponge  or  soft  clean  chamois,  wetted  and  thoroughly 
squeezed  out,  the  excess  water  should  be  wiped  carefully  off  both  sides  of 
the  film  in  one  slow,  gentle  and  uniform  stroke  for  each  side.  A  well  hard- 
ened film  should  dry  of  its  own  accord  in  20  to  SO  minutes  after  being 
suspended.  For  quick  drying  an  electric  fan  may  be  used,  provided  one  is 
sure  the  fan  will  not  direct  a  stream  of  dust  onto  the  film.  Dust  particles 
hurled  at  the  delicate  gelatine  surface  will  become  imbedded  in  it  beyond 
hope  of  removal.  It  is  therefore  preferable  that  the  current  of  air  strike 
the  uncoated  celluloid  back  side  of  the  film. 

Soaking  a  Film  Before  Development 

Unless  the  exposed  film  is  old  and  brittle  it  should  not  be  soaked  in 
water  before  development.  There  seems  to  be  no  advantage  in  pre- 
soaking  a  film  to  be  developed.  It  would  be  just  one  unnecessary  opera- 
tion. The  old  contention  in  favor  of  such  a  procedure  was  that  it  pre- 
vented formation  of  air  bells  and  enabled  the  developer  to  start  work 
more  quickly  and  uniformly  by  presoftening  the  emulsion.  Air  bells  are 
successfully  eliminated  by  agitating  the  developer  as  soon  as  it  is  poured 
into  the  tank;  while  the  developer  needs  no  presoftening  of  the  emulsion  to 
start  its  uniform  action  which  is  to  continue  for  some  twenty  minutes 

It  is  one  of  the  features  of  the  technique  offered  here  to  develop  a 
Leica  film  with  the  utmost  simplicity  and  effectiveness,  with  complete  elim- 
ination of  all  steps  of  doubtful  value. 

Step  by  Step  Developing  Procedure 

To  develop  a  roll  of  Leica  film  proceed  as  follows : 

Step  1.  In  total  darkness  wind  film  onto  the  spool  of  the  developing 
tank,  emulsion  side  in  (facing  center  of  reel).  To  do  so, 
do  not  pull  the  film  out  of  the  closed  or  partly  opened 
magazine.  Open  the  magazine,  take  the  spool  out  and  hold 
it  in  the  palm  of  the  hand  while  rewinding  it  onto  the  reel 
of  the  developing  tank.  Be  sure  to  close  tank  carefully 
and  securely  before  turning  on  light. 


Film  Development 

Step  2.  Cool  developer  to  exact  temperature  required  for  given 
developer.  While  cooling  developer,  prepare  short-stop 
bath  and  the  hypo.  Short-stop  bath  should  be  about  the 
temperature  of  the  developer.  Hypo  not  less  than  65°F. 
(18°C.)  or  more  than  70°F.  (21°C.). 

Step  3.  Pour  developer  in  steady  stream  into  developing  tank. 
Directly  after  filling  tank,  observe  time  on  clock  and  start 
agitating  developer.  Agitate  for  about  one  minute,  not 
vigorously  but  steadily  to  prevent  formation  of  air  bells. 
Agitate  every  three  to  five  minutes  thereafter. 

Step  4.  One-half  minute  before  expiration  of  full  time  called  for 
by  developing  formula,  start  pouring  out  developer  from 
the  tank  (pour  into  original  storing  container,  unless  de- 
veloper life  is  exhausted) .  Shake  all  developer  carefully 
out  of  tank. 

Step  5.  Without  rinsing,  pour  the  short-stop  bath  into  tank  in  a 
steady  stream.  Observe  time  on  clock  and  start  agitating 
for  about  one  minute.  Leave  short-stop  in  tank  for  five 
minutes,  agitating  occasionally.  Pour  it  off  at  expiration 
of  time.  The  short-stop  should  be  used  once  only. 

Step  6.  Pour  in  hypo  without  rinsing  tank.  Start  agitating 
directly  after  tank  is  filled  with  hypo  and  continue  every 
two  or  three  minutes.  Fresh  hypo  should  remain  in  tank 
for  10  minutes.  At  the  end  of  10  minutes,  pour  off  hypo. 
Hypo  should  not  be  used  for  fixing  film  more  than  twice 
(preferably  once).  It  can  then  be  used  for  fixing  out 

Step  7.  After  pouring  out  hypo,  fill  the  tank  with  running  water. 
Adjust  it  to  a  temperature  of  between  65°F.  (18°C.)  and 
70°F.  (21°C).  Water  colder  than  65°F.  will  not  wash 
the  film  properly;  warmer  than  70°F.  it  is  likely  to  soften 
the  film.  After  filling  tank  with  water,  agitate  it  briefly 
but  vigorously,  pour  oui  water  and  put  tank  under  tap, 
letting  the  water  run  down  in  a  steady  stream  for  about 
twenty  to  thirty  minutes. 

Step  8.  Remove  film  from  tank.  Hang  it  by  film  clips  in  a  cool, 
dry,  dust-free  place  and  wipe  off  excess  water  gently  from 
both  surfaces  of  film  by  means  of  Viscose  Sponge.  The 
sponge  should  be  wet,  but  thoroughly  squeezed  out.  When 
wiping  emulsion  side  only  the  gentlest  pressure  should  be 


exerted  to  prevent  scratching.  The  celluloid  side  of  the 
film  should  be  dried  thoroughly  with  slightly  more  pres- 
sure. Film  will  dry  normally  in  twenty  to  thirty  minutes, 
but  it  is  best  to  let  it  hang  for  about  three  times  the  length 
of  time  it  requires  for  the  film  to  become  concave  with 
respect  to  the  emulsion  side. 

Step  9.  Boll  film  carefully,  emulsion  side  in,  and  store  it  in  a  dry, 
dust-free,  clean  box.  A  small  rubber  band  slipped  over  the 
roll  will  prevent  film  from  scratching. 

Step  10.  It  is  best  not  to  put  the  film  into  an  enlarger  for  from  six 
to  twelve  hours  after  it  has  dried  out.  Objectionable 
Newton  rings  will  form  if  "  green "  film  is  placed  in  the 

Complete  Procedure  for  REVERSAL  of  Agfa  Superpan  Reversible  Film 

Keversible  Superpan  should  be  handled  in  total  darkness.  It  can,  however, 
be  desensitized  in  a  1:2000  Pinakryptol  Green  Solution  for  two  minutes, 
and  then  handled  in  bright  green  light  such  as  the  Agfa  #103  green  safe- 
light  with  a  25  W.  bulb. 

The  reversal  procedure  is  divided  into  six  basic  operations,  which  are  inter- 
spersed with  appropriate  periods  of  washing  in  running  water. 

First  Developer. 

Avoirdupois  Metric 

Water  (125°  F.  or  52°  C.) 24  ounces  750.0  cc 

Metpl 30  grains  2.0  grams 

Sodium    Sulphite    1  ounce  30.0  grams 

Hydroquinone 180  grains  12.0  grams 

Potassium    Bromide    120  grains  8.0  grams 

Sodium  Hydroxide 265  grains  18.0  grams 

Potassium    Sulphocyanate    75  grains  5.0  grams 

Cold  Water  to  make  32  ounces  1000.0  cc 

Develop  normally  exposed  film  for  6  minutes  at  65°  F.  or  18°  C.  with  constant 
though  not  too  rapid  agitation.  Do  not  use  this  developer  more  than  once  for 
consistently  good  results. 

Wash  film  in  running  water  for  10  minutes. 

The  accuracy  of  the  first  development  and  the  thoroughness  of  washing  following 
it  are  the  two  most  important  steps  in  the  entire  procedure. 


Film  Reversal 

Reversal  Bath  (Bleach) 

Water   to   make    32  ounces       1000.0  cc 

Potassium   Bichromate    75  grains  5.0  grams 

Sulphuric  Acid  (Concentrated)    1.3  drams  5.0  cc 

Add  Sulphuric  acid  last,  pouring  it  slowly  while   stirring-. 

Agfacolor    Plate    Reversing   Salts   put    up    in    tubes,    ready    to   be    dissolved    in    18 

ounces  of  water  may  be  substituted  for  above  reversal  bath. 

After  the  film  has  remained  in  the  Reversal  Bath  for  at  least  2  minutes, 
white  light  may  be  turned  on  in  the  darkroom,  and  the  remainder  of  the 
procedure  may  be  conducted  in  white  light. 

Carry  on  reversal  until  both  the  negative  image  and  the  anti-halation  under- 
coating  are  dissolved  leaving  only  the  undeveloped  silver  haloid.  This  requires 
about  5  minutes. 

"Wash  film  in  running  water  for  5  minutes. 

Clearing  Bath 

Water  to   make    32  ounces       1000.0  cc 

Sodium  Sulphite    (dessicated)    1 2/3  ounces    50.0  grams 

Clear  in  above  solution  for  5  minutes.  Yellow  stain  is  gradually  removed  and 
the  emulsion  assumes  a  clear  white  color. 

Wash  in  running  water  for  2  minutes. 


Thoroughly  expose  film  to  white  light  of  a  200  watt  bulb  or  of  a  Photoflood  bulb 
(either  bulb  should  be  placed  in  a  reflector).  Hold  film  about  6  feet  away  from 
light,  rotating  it  so  that  its  entire  surface,  both  front  and  back,  Is  thoroughly  exposed. 
Exposure  required:  2-3  minutes.  Direct  sunlight  should  not  be  used.  Film  should  not 
be  held  too  closely  to  light  source  to  avoid  injury  to  emulsion  from  heat. 


Second  Developer 

Water  (at  125°  F.  or  52°  C.) 24  ounces  750.0  cc 

MetoJ    30  grains  2.0  grams 

Sodium   Sulphite    (dessicated)    370  grains  25.0  grams 

Hydroquinone    60  grains  4.0  grams 

Sodium  Carbonate   (monohydrated)    . . .  295  grains  20.0  grams 

Potassium    Bromide    30  grains  2.0  grams 

Cold  water  to  make    32  ounces  1000.0  cc 

Develop    until    image    has    become    thoroughly    blackened,     which  requires    about 
5  minutes. 

Rinse  in  running  water  for  3-5  minutes. 


6.    FIXING 

Fix  for  five  minutes  in  regular  acid  hardening  fixing  hypo  bath   (p.   123). 

Wash   in   running  water  for   10-15   minutes. 

Wipe  off  surface  water  gently  with  the  aid  of  viscose  sponge. 

Hang  up  film  to  dry. 

All  solutions  and  the  running  water  should  be  maintained  throughout  the 
procedure  at  65°  F.  or  18°  C.  Utmost  cleanliness  is  required  for  success- 
ful results.  Avoid  contamination  of  solutions  through  carrying  one  into 

General  Suggestions 

Utmost  cleanliness  should  be  observed  throughout  processing  of  Leica 

Use  only  the  best  and  purest  chemicals,  and  once  a  brand  is  adopted 
continue  to  use  it  for  uniform  results. 

Observe  greatest  accuracy  in  weighing  and  measuring  chemicals. 

Never  permit  fingers  to  come  in  contact  with  emulsion  side  of  film 
either  before  or  after  developing. 

Never  handle  film  except  by  its  edges. 

If  film  becomes  soiled,  wipe  it  carefully  with  a  soft  chamois  skin 
dipped  in  a  suitable  film  cleaner  (see  page  130). 

Apron  of  Correx  tank  should  be  removed  when  not  in  use,  and  kept 
suspended  by  one  or  both  its  ends. 

Films  should  be  kept  as  far  away  as  possible  from  heat,  radiators,  hot 
water  pipes,  etc.  It  should  be  remembered  that  most  of  our  negative  ma- 
terial is  nitrate  stock  and  highly  inflammable.  Therefore  films  should  be 
kept  in  a  well  ventilated  cool  dark  place,  away  from  open  flame. 

Developing  and  handling  of  Leica  negatives  should  not  be  turned  into 
an  obsession,  but  should  be  considered  as  only  one  of  the  factors  which 
contributes  towards  the  final  picture. 


Reticulation  is  a  peculiar  phenomenon  occurring  on  films,  and  in  the 
case  of  Leica  films  it  may  actually  ruin  an  otherwise  perfect  negative. 
It  is  due  to  local  strains  in  the  gelatine  which  may  be  caused  by  a  sudden 
change  in  temperature  of  solutions,  or  atmospheric  conditions.  It  occurs 
in  different  degrees,  from  an  extremely  mild  form  barely  distinguishable 
by  the  eye,  to  a  very  severe  form.  Reticulation  looks  like  miniature  ele- 
phant skin  shrivelled  into  a  labyrinth-like  pattern.  In  its  severest  form 
it  produces  actual  tiny  cracks  in  the  emulsion;  the  accompanying  illustra- 
tion shows  this  condition. 

Reticulation  can  happen  at  any  point  during  processing  of  film,  in- 
cluding pre-soaking,  during  development,  or  at  the  point  of  change  from 
developer  to  hypo.  It  can  even  occur  while  the  finished  film  is  drying. 

To  minimize  the  danger  of  reticulation,  the  pre-soaking  of  the  film, 
and  its  washing  between  solutions  should  be  entirely  eliminated.  The  use 
of  the  short-stop  as  an  intermediate  bath  between  the  developer  and  hypo 
cannot  be  recommended  strongly  enough.  The  chrome  alum  and  sodium 
bisulphite  short-stop  has  a  beneficial  effect  upon  the  film  by  its  gentle 
hardening  and  slightly  acid  action  as  a  transition  from  the  alkaline  de- 
veloper to  the  highly  acid  hardening  fixing  bath.  It  is  believed  that  the 
short-stop  carried  over  in  small  quantities  into  the  hypo  bath  corrects 
the  acidity  of  the  latter  to  the  point  where  it  will  not  cause  reticulation* 


Film  Development 

Fig.  87    Reticulation,  mild  Fig.  88     Reticulation,  acute— 

(Anonymous!)  cracks  in  emulsion 

(Anonymous ! ) 
Newton  Rings 

Another  source  of  considerable  annoyance  are  the  so-called  Newton 
rings.  These  are  irregular  spots  of  all  colors  of  the  spectrum  appearing 
on  the  surface  of  the  enlarging  paper  while  the  negative  is  in  the  enlarger 
for  printing.  In  appearance  these  Newton  rings  suggest  those  charac- 



Fig.  89    Masking  plate  for  elimination  of  Newton  Rings,  actual  size  for 


texistic,  rather  pretty,  patterns  which  oil  forms  on  water.  While  pretty 
to  look  at,  Newton  rings  are  a  decided  nuisance  for  they  will  ruin  any 
print,  and  are  hard  to  eliminate. 

They  occur  particularly  on  "green"  film,  that  is,  film  that  has  just 
been  dried  but  still  contains  moisture.  For  this  reason  it  is  recommended 
that  films  not  be  put  into  the  enlarger  for  six  to  twelve  hours  after  drying. 

Newton  rings  are  actually  caused  by  the  condenser  of  the  enlarger 
not  being  in  perfect  contact  with  the  entire  back  of  the  film,  but  merely 
touching  it  at  several  points,  indicating  that  the  film  is  not  in  a  true  plane. 

Of  most  remedies  suggested  for  correction  of  this  annoying  condition 
the  one  providing  a  special  mask  or  spacer,  as  shown  in  the  cut  which  is 
a  full  size  tracing,  is  the  most  practical.  This  masking  plate  can  be  made 
from  a  thoroughly  fogged,  developed  and  fixed  out  piece  of  cut  film,  with 
the  aid  of  a  sharp  razor  blade.  The  regular  masking  negative  carrying 
plate  is  taken  out  of  the  enlarger,  the  film  placed  over  it  as  usual  emulsion 
side  down,  and  the  special  mask  placed  over  the  negative;  the  entire  as- 
sembly is  then  slipped  into  the  enlarger  and  from  this  point  the  procedure 
is  Carried  on  as  usual. 

Film  Cleaner 

Film  that  is  dusty,  dirty,  shows  finger  marks,  lint,  etc.,   should  be 
carefully  cleaned  before  placing  it  in  the  enlarger. 

An  excellent  all-around  film  cleaner  is  easily  prepared  as  follows: 
Ethyl  Alcohol  (pure  grain  alcohol) ...  85%  (or  parts) 

Methyl   Alcohol    (wood   alcohol) 10%   (or  parts) 

Strong  Ammonia   5%  (or  parts) 

This  cleaner  is  not  "dry",  as  is  carbon  tetrachloride  and  similar  cleaners. 
Because  this  cleaner  is  "wet",  it  does  not  charge  the  film  electrically,  thus 
leaving  it  without  the  usual  tendency  to  attract  lint  and  dust  from  the 
air.  This  cleaner  should  be  applied  to  both  surfaces  of  the  film  with  a 
clean,  lintless  fine  linen  cloth,  soft  chamois  or  lens  tissue. 

Reducing  or  Intensifying  Leica  Negatives 

These  two  processes  are,  to  say  the  least,  dangerous  for  miniature 
camera  work,  and  their  use  is  definitely  discouraged.  Either  of  these  pro- 
cesses increases  the  grain  considerably  and  destroys  definition.  However, 
for  those  who  wish  to  save  a  valuable  negative,  the  two  formulas  most 
suitable  for  miniature  camera  work  are  offered: 


Stock  Solution  A 

Avoirdupois  Metric 

Water    32      ounces  1.0  liter 

Potassium  Permanganate    4      grains  0.3  gram 

Sulphuric  Acid   (10%    solution) Yz  ounce '  I6J3~ccT 

Stock  Solution  B 

Water    f ..."".;  77 "96"     ounces  SrOHDSers 

Ammonium  Persulphate 3      ounces          90.0  grams 

For  use,  take  one  part  of  A  to  three  parts  of  B.  When  sufficient  reduction  is 
secured  the  negative  should  be  cleared  in  a  1%  solution  of  sodium  bisulphite. 
Wash  the  negative  thoroughly  before  dryinjr. 


Film  Intensification 


For  35mm  Negative  and  Positive  Films 

The  following  formula  is  the  only  intensifier  known  that  will  not 
change  the  color  of  the  image  on  positive  film  on  projection.  It  gives 
proportional  intensification  and  is  easily  controlled  by  varying  the  time  of 
treatment.  The  formula  is  equally  suitable  for  positive  and  negative  film. 

*Stock  Solution  No.  1 


Silver  Nitrate   2      ounces 

Distilled  water  to  make 32      ounces 

*  Store  in  a  brown  bottle. 

Stock  Solution  No.  2 
Sodium  Sulphite,  desiccated. 2 

Water  to  make. 



Stock  Solution  No.  3 

Hypo    3 1/2  ounces 

Water  to  make 32      ounces 

60.0  grams 

1.0  liter 

60.0  grams 
1.0  liter 

105.0  grams 
1.0  liter 

Stock  Solution  No.  4 

Sodium  Sulphite,  desiccated l/2  ounce  15.0  grams 

Metol   350      grains  24.0  grams 

Water  to  make 96      ounces  3.0  liters 

Prepare  the  intensifier  solution  for  use  as  follows :  Slowly  add  1  part  of  solu- 
tion No.  2  to  1  part  of  solution  No.  1,  shaking  or  stirring  to  obtain  thorough 
mixing.  The  white  precipitate  which  appears  is  then  dissolved  by  the  addition 
of  1  part  of  solution  No.  3.  Allow  the  resulting  solution  to  stand  a  few  min- 
utes until  clear.  Then  add,  with  stirring,  3  parts  of  solution  No.  4.  The 
intensifier  is  then  ready  for  use  and  the  film  should  be  treated  immediately. 
The  degree  of  intensification  obtained  depends  upon  the  time  of  treatment 
which  should  not  exceed  25  minutes.  After  intensification,  immerse  the  film 
for  2  minutes  with  agitation  in  a  plain  30%  hypo  solution.  Then  wash  thor- 

Storage  and  Preservation  of  Films 

This  matter  is  again  a  question  of  personal  preference.  The  writer 
knows  of  as  many  storing  and  filing  systems  as  he  knows  Leica  workers. 
There  are  transparent  cellophane  envelopes  in  book  or  box  form  holding 
strips  of  from  three  to  eight  negatives.  There  are  books  with  flaps  of 
transparent  paper  and  books  with  pockets.  There  are  filing  cabinets  and 
chests  of  endless  variety. 

Personally,  the  writer  prefers  to  preserve,  store  and  file  Leica  nega- 
tives in  uncut  lengths,  in  rolls  firmly  but  not  tightly  wound.  A  small  rub- 
ber band  (about  Vzn  diameter)  is  slipped  around  the  roll  before  placing 
it  in  a  steel  box  divided  into  small  sections  of  twenty-five  to  a  box.  Each 
roll  is  given  a  number  and  a  brief  description  of  the  entire  roll  marked 
under  the  corresponding  number  on  ihe  inside  lid  of  the  box.  Each  box 
is  marked  with  an  alphabet  number  and  a  record  kept  in  a  loose  leaf 
scrap  book  into  which  contact  prints  from  every  roll  are  pasted. 

The  Negative  Viewer  and  Marker  is  Con- 
venient for  Examining  Completed  Films 






Probably  'everyone  who  (has  ever  made  a  Leica  shot  and 
" blown  it  up"  to  a  good  sized  enlargement  has  wished  for  an 
opportunity  to  do  a  bit  of  retouching  on  minor  parts  of  the  nega- 
tive. But  a  microscopic  eye  is  needed  for  work  as  exacting  as  this 
and  retouching  and  spotting  have  as  a  result  been  relegated  to  the 
final  print. 

Many  a  cynical  megacamist  has  seized  this  apparent  fault  as 
the  clinching  point  in  his  arguments  against  "postage  stamp'7 
negatives.  And  this  with  little  reason,  for  there  are  three  ways 
by  which  Leica  photographs  may  be  conveniently  put  into  the  form 
of  enlarged  negatives  for  retouching  before  the  final  print  or  en- 
largement is  made. 

Retouching,  however,  is  not  the  only  advantage  offered  by  the 
use  of  enlarged  negatives — for  they  come  in  handy  in  many  ways. 
Whenever  several  enlargements  requiring  dodging  or  projection 
control  are  desired  to  be  made  identical  with  one  another,  the  use 
of  an  enlarged  negative  not  only  simplifies  the  procedure  and  cuts 
the  over-all  working  time,  but  it  insures  the  uniformity  of  the  final 
prints.  All  the  dodging  and  retouching  may,  for  example,  be  done 
upon  one  master  enlarged  negative  of  from  4x5  to  8  x  10  inches 
in  size,  and  all  prints  of  any  size  may  be  contact  printed,  enlarged, 
or  reduced  from  this  with  unvarying  results.  The  contrast  of  ori- 
ginals that  are  too  dense  or  too  flat  may  also  be  Improved  in  the 
preparation  of  the  enlarged  negative.  Furthermore,  enlarged  nega- 
tives offer  an  excellent  medium  for  the  combination  of  parts  of 
different  negatives  when,  as  is  sometimes  the  case,  the  final  print 
is  built  of  several  separate  images. 

There  are  three  methods  which  may  be  used  to  obtain  good 
enlarged  negatives  without  excessive  time  or  trouble  in  processing. 

The  first  involves  the  use  of  a  new  and  .singular  photographic 
m^'erial,  "Direct  Copy  Film".  This  unusual  film  produces  a 
negative  directly  from  a  negative — although  it  is  processed  in  a 
manner  no  different  than  that  regularly  used  for  chloride  printing 


The  second  method  is  based  upon  the  use  of  a  reversible  film 
for  the  original  exposure  in  the  Leica.  Upon  special  development, 
this  reversible  film  produces  a  positive  (normally  used  for  pro- 
jection purposes)  which  is  then  enlarged  on  a  process  or  commercial 
film  to  give  the  enlarged  negative. 

The  third  method  embraces  the  preparation  of  an  intermediate 
film  positive  from  which  the  enlarged  negative  is  made.  This  is 
naturally  the  longest  process  in  point  of  time  but  it  is  well  known 
and  will  do  the  trick  admirably  if  the  special  films  required  for 
either  of  the  first  two  methods  are  not  obtained. 

Direct  Copy  Film  is  a  new  material  which  is  being  manufactured  by 
the  Agfa  Ansco  Corporation  of  Binghamton,  N.  Y.  The  emulsion  of  this 
remarkable  film  has  properties  by  means  of  which  it  can  produce  in  one 
single  exposure  and  development  a  negative  from  a  negative  (or  for  that 
matter,  a  positive  from  a  positive).  The  emulsion  of  the  film  is  treated 
during  manufacture  so  that  when  developed  without  any  exposure  what- 
soever, a  maximum  density  of  opaque  silver  is  produced.  However,  for 
every  increasing  amount  of  exposure  the  film  shows  a  corresponding 
increase  in  transparency  after  development.  Thus,  light  parts  of  an  ori- 
ginal are  duplicated  by  transparent  portions  of  the  copy  film  and  shadow 
regions  of  the  original  are  represented  with  equal  accuracy.  Aside  from 
this  unusual  characteristic  the  emulsion  of  Direct  Copy  Film  resembles 
a  chloride  printing  paper  in  color  sensitivity,  required  exposure,  and  gen- 
eral handling  and  processing  in  the  darkroom.  Because  Direct  Copy  Film 
has  an  extremely  fine-grained  emulsion  no  additional  graininess  is  pro- 
duced in  the  final  enlargement  by  this  method. 

Because  of  its  peculiar  properties,  Direct  Copy  Film  makes  the  prep- 
aration of  enlarged  negatives  a  rapid  and  simple  procedure.  The  only 
operations  requiring  special  mention  are  those  of  exposure  and  develop- 
ment. Fixation  and  washing  are  done  in  the  conventional  manner. 

Since  Direct  Copy  Film  has  approximately  the  same  speed  as  the 
standard  soft  grades  of  contact  printing  paper,  Leica  negatives  may  be 
enlarged  onto  it  without  unduly  long  exposures  when  a  photoflood  bulb  is 
used  in  the  enlarger.  A  small  strip  of  chloride  printing  paper  such  as 
Convira  may  be  used  in  making  a  preliminary  test  exposure,  and  the  cor- 
rect printing  time  determined  from  the  test  exposure.  The  piece  of  Direct 
Copy  Film  should  be  mounted  on  the  enlarging  easel  with  the  emulsion 
side  up.  The  Leica  negative  to  be  enlarged  should  be  inserted  in  the  en- 
larger,  not  in  the  usual  way,  but  with  the  emulsion  side  facing  upward 
instead  of  downward.  This  will  give  a  reversed  (from  left  to  right)  image 
on  the  easel  and  a  correct  image  in  the  final  print.  The  density  of  the 
enlarged  negative  should  be  controlled  by  adjusting  the  exposure  and  not 
by  modification  of  the  developing  time.  Thin  copy  negatives  indicate 
over-exposure,  while  an  enlarged  negative  that  is  too  dense  is  the  result 
of  under-exposure.  Amber  or  bright  orange  light  may  be  used  in  the 


Enlarged  Negatives 

Development  of  the  enlarged  negative  on  Direct  Copy  Film  can  be 
carried  out  in  any  soft-working  film  developer,  but  the  two  following 
formulas  are  recommended  for  best  results. 

For  Normal  Gradation  on  Direct  Copy  Film 

Avoirdupois  Metric 

Water   to   make    32  ounces  1.0  liter 

Metol     23  grains  1.5  grams 

Sodium  Sulphite,   anhydrous    ......        2  oz.  290  gr.  80.0  grams 

Hydroquinone     45  grains  3.0  grams 

Borax     45  grains  3.0  grams 

Potassium  Bromide    •  •        8  grains  0.5  grams 

Use  without  dilution.    Develop  12  to  20  minutes  at  5°  F.  (18°  C.)- 

For  Moderate  Brilliance  on  Direct  Copy  Film 

Avoirdupois  Metric 

Water    (lukewarm) 32  ounces  1.0  liter 

Metol     90  grains  6.0  grams 

Sodium  Sulphite,   anhydrous    6  ounces  180.0  grams 

Sodium  Bisulphite    60  grains  4.0  grams 

Hydroquinone 180  grains  12.0  grams 

Sodium  Carbonate,  monohydrated   .   360  grains  24.0  grams 

Potassium   Bromide    48  grains  3.2  grams 

Add  cold  water  to  make   1  gal.  4.0  liters 

Use  without  dilution.    Develop  8  to  10  minutes  at  65°F.  (18°  C.). 

As  mentioned  above,  variations  in  results  should  be  controlled  more 
by  adjustment  of  exposure  rather  than  by  modification  of  developing 
time.  Best  results  will  be  obtained  by  keeping  within  the  times  recom- 
mended for  each  developer.  Stains  will  be  avoided  by  the  use  of  a  con- 
ventional acid  short  stop  bath  between  development  and  fixation. 

Enlarged  Negatives  from  Reversible  Film  Originals 

The  second  method  of  preparing  enlarged  negatives  relies  upon  the 
use  of  a  reversible  film  in  the  Leica  for  the  original  exposure.  This  film 
is  developed  by  a  reversal  process  to  a  positive,  usually  for  projection 
purposes.  A  film  of  this  kind,  prepared  especially  for  the  Leica,  is  made 
by  the  Agfa  Ansco  Corporation  of  Binghamton,  N.  Y.,  and  is  sold  under 
the  name  of  Superpan  Reversible.  It  is  a  high  speed,  panchromatic 
material  which  may  be  compared  to  the  supersensitive  type  in  group  1 
(see  pages  101,  104).  Because  it  is  a  reversal  film  it  gives  positives 
which  have  an  exceptional  fineness  of  grain — a  noteworthy  point  for  all 
miniature-camera  work.  The  positive  resulting  from  the  processing  of 
the  Superpan  Reversible  Film  can  be  easily  enlarged  onto  a  piece  of 
Commercial,  Commercial  Ortho  or  Process  Cut  Film  and  developed  in  a 
standard  negative  film  developer.  The  exposure  required  by  Process  Film 
will  be  about  the  same  as  that  needed  for  the  faster  grades  of  Bromide 
enlarging  paper,  while  Commercial  and  Commercial  Ortho  Film  will 
require  about  one-tenth  as  much  exposure. 


The  processing  of  the  reversible  film  original  will  be  done  at  a  nom- 
inal charge  by  the  film  manufacturer  but  it  can  be  carried  out  satisfactor- 
ily in  about  two  hours  by  the  procedure  outlined  in  detail  on  page  126 
of  this  volume. 

Enlarged  Negatives  by  the  Positive-Negative  Process 

The  third  method  by  which  enlarged  negatives  may  be  made  from 
Leka  originals  requires  the  preparation  of  an  intermediate  positive  film. 
This  may  be  made,  of  course,  by  contact  printing  onto  35mm.  positive 
film  stock  and  proceeding  as  with  the  reversible  film  positive.  However, 
greater  convenience  is  undoubtedly  afforded  by  the  preparation  of  the 
intermediate  film  positive  in  an  enlarged  form.  This  is  easily  done  by 
enlarging  the  original  Leica  negative  onto  a  sheet  of  Process  or  Commer- 
cial Film  instead  of  the  usual  bromide  paper.  Development  can  be  carried 
out  in  a  conventional  negative  film  developer  such  as  the  following: 

Avoirdupois  Metric 

Water    (lukewarm) 32  ounces  1      liter 

Metol      90  grains  6      grams 

Sodium  Sulphite,  anhydrous    6  ounces  180      grams 

Sodium    Bisulphite    60  grains  4      grams 

Hydroquinone     180  grains  12      grams 

Sodium  Carbonate,  monohydrated . .   360  grains  24      grams 

Potassium  Bromide    48  grains  3.2  grams 

Add  cold  water  to  make 1  gal.  4      liters 

TRAY  DEVELOPMENT:  Use  full  strength.  Normal  devel- 
opment time,  5  to  7  minutes  at  65°F. 

TANK  DEVELOPMENT:  Dilute  one  part  above  developer  to 
one  part  water.  Normal  development  time,  12  to  14  minutes  at 

This  enlarged  positive  film  when  fixed,  washed  and  dried  can  then  be 
contact  printed  or  enlarged  onto  another  piece  of  Process  or  Commercial 
Film  to  produce  the  final  enlarged  negative.  Retouching  and  dodging 
can,  of  course,  be  done  at  either  of  the  two  intermediate  steps — inter- 
mediate positive,  or  final  enlarged  negative.  If  Process  Film  is  used  for 
both  intermediate  positive  and  final  master  negative,  developing  time 
should  be  decreased  to  avoid  results  of  excessive  contrast. 

EDITOR'S  NOTE:  For  finer  gradation,  softness  and  minute  details 
expected  of  pictorial  work,  it  may  be  found  that  substitution  of  the  posi- 
tive Process  or  Commercial  film,  suggested  by  the  author,  by  a  softer  film 
may  be  more  effective.  Reference  is  made  to  the  type  of  film  offered  by 
orthochromatic  emulsions  such  as  Eastman  Portrait  or  Safety  Ortho  films, 
Agfa  Plenachrome  or  Defender  Pentagon.  These  films  are  more  sensitive 
to  light  in  general  and  a  shorter  exposure  is  required  than  for  the  positive 
film.  The  Safelight,  of  course,  would  need  to  be  changed  from  yellow  to 
ruby,  according  to  recommendations  contained  in  each  package  of  film. 
Otherwise,  the  procedure  is  not  different  from  that  outlined  by  the  author. 



A  photographic  darkroom  can  be  the  source  of  many  enjoyable 
hours.  Here  is  a  place  where  you  can  try  out  some  of  those  new 
photographic  ideas  of  yours,  make  your  exhibition  enlargements,  try 
out  the  latest  developing  formula,  make  photo-montages,  lantern 
slides,  develop  color  film,  and  experiment  with  various  enlarging 
papers.  As  you  complete  your  darkroom  it  will  quickly  become  the 
meeting  place  for  your  friends  who  have  similar  interests.  After  a 
hectic  day  at  the  office  or  some  other  occupation  the  evening  hours 
in  your  darkroom  will  be  one  of  the  most  enjoyable  relaxations  you 
can  experience. 

Make  the  darkroom  a  model  of  convenience,  cleanliness,  and  neat- 
ness. If  you  cannot  find  space  for  a  separate  room  for  your  work 
don7t  worry  but  fix  up  the  kitchen  sink  for  your  developing  and  en- 
larging equipment.  Dark  shades  over  the  windows  will  exclude  all 
light,  and  the  darkroom  safety  light  may  be  easily  installed  over 
the  sink.  If  the  kitchen  is  not  convenient  explore  the  bathroom  and 
confiscate  one  corner  for  your  equipment.  A  wide  board  over  the 
bathtub  will  hold  several  trays,  while  the  bathtub  and  sink  may  be 
used  for  washing  the  prints  or  films.  There  are  thousands  of  if  bath- 
tub finishers"  located  in  every  section  of  the  country  who  are  doing 
excellent  photographic  work.  The  writer  belonged  to  this  fraternity 
of  "bathtub  finishers''  for  many  years  before  he  had  an  opportunity 
to  enjoy  the  thrills  of  having  a  separate  darkroom  completely 
equipped  for  his  work. 

If  you  happen  to  be  living  in  a  small  apartment  and  wonder 
how  you  can  solve  the  darkroom  situation  try  converting  the  kitchen- 
ette into  a  darkroomette.  Such  a  transformation  has  been  cleverly 
done  by  John  T.  Moss,  Jr.  of  New  York.  The  accompanying  photo- 
graph will  give  a  complete  plan  of  Mr.  Moss's  darkroomette.  Note 
that  the  folding  doors  may  be  closed  or  opened  as  required.  The 
refrigerator  can  be  used  for  keeping  solutions  cool,  or  it  may  be  a 
source  of  ice  cubes  when  required.  It  is  surprising  how  small  a  space 


can  be  utilized  for  doing  all  one's  developing  and  enlarging  work, 
so  don't  let  the  space  problem  worry  you  when  yon  set  up  a  place  to 
do  your  finishing  work.  J.  Harlan  Davis  of  Mt  Vernon,  Ohio  has 
solved  his  space  problem  by  constructing  a  * 'folding  darkroom'5 
right  in  his  library.  He  has  constructed  a  wall  cabinet  which  holds 
all  his  equipment,  and  the  door  swings  down  to  make  the  work  table. 

Fig.  92  "Darkroomette" 
of  John  T.  Moss/  Jr.,  util- 
izing facilities  of  the  mod- 
ern kitchenette 

A  Model  Darkroom 

In  order  that  we  may  obtain  a  complete  picture  of  what  an 
amateur  darkroom  should  look  like  let's  take  the  model  darkroom 
recently  constructed  by  Lee  Parsons  Davis  of  New  Bochelle,  N.  Y. 
The  accompanying  photographs  and  drawings  will  give  you  complete 
information,  even  better  than  any  long  detailed  descriptions.  Mr. 
Parsons  based  his  plans  upon  a  similar  darkroom  constructed  by 
Clifford  H.  Beegle  of  Beaver  Falls,  Pa. 

The  inside  dimensions  of  Mr.  Parsons'  darkroom  are  seven  feet 
by  six  feet.  Although  this  space  may  at  first  seem  small  it  is  sur- 
prising how  much  room  there  is  to  work  and  also  how  much  space 
there  is  for  storing  equipment  and  supplies.  The  secret  of  this  space 
utilization  is  that  there  are  many  storage  drawers,  and  several  shelves 
for  chemical  storage.  Space  has  been  made  for  print  drying  racks, 


Leica  Darkroom 

ferrotype  tins,  and  a  large  sink  five  feet  long  by  sixteen  inches  wide 
and  one  foot  deep.  The  sink  is  constructed  of  California  white  pine 
1*4  inches  thick.  The  side  and  end  boards  are  12^  inches  wide,  and 
the  bottom  is  one  wide  board.  These  boards  were  grooved  to  fit  at 
a  planing  mill,  and  set  together  without  glue  or  nails,  then  bolted 
on  the  ends  and  bottom. 

There  are  three  faucets  over  the  sink,  two  of  which  are  combina- 
tion faucets  which  permit  the  proper  temperature  regulation  of  the 
water.  One  of  the  faucets  has  a  small  under  valve  which  permits  an 
outlet  for  tray  washing  of  prints  as  shown  in  the  accompanying  illus- 
tration. A  removable  drainboard  for  the  sink  provides  for  additional 
working  space  when  required.  The  11  by  14  inch  developing  trays 
will  fit  across  the  sink  while  the  space  below  can  be  used  for  a  larger 
washing  tray.  Plenty  of  electrical  connections,  safety  lights,  as  well 
as  the  regular  white  lights  are  provided. 

Finally,  and  one  of  the  most  important  points  to  consider  in  the 
darkroom  is  the  ventilation.  A  fresh  air  inlet  has  been  provided  for 
through  the  door  of  the  darkroom,  while  the  foul  air  is  sucked  out 
through  a  light-tight  duct  by  an  electric  fan.  This  permits  constant 
circulation  of  air,  and  when  two  or  three  people  are  working  in  the 
darkroom  at  one  time  there  is  always  plenty  of  good  clean  air. 

Fig.  93     Interior   of   photographic 
laboratory   of  Lee  Parsons  Davis. 

Fig.  94    Outside  of  Mr.  Davis'  pho- 
tographic laboratory  showing  posi- 
tion of  exhaust  fan. 
Note  light  trap  ventilator  on  door. 


Fig.  95    Elevation  facing  work  bench  showing  enlarging  table,  cabinets 
and  cross-section  of  sink 

Key  to  drawings  (figures  95,  96,  97) : 

No.  10 
No.  11 
No.  12 
No.  13 
No.  14 
No.  15 
No.  16 
No.  17 
No.  IS 
No.  19 
No.  20 
No.  21 
No.  22 
No.  23 
No.  24 
No.  25 
No.  26 
No.  27 
No.  28 

No.  29 
No.  30 

Work  tench  and  cabinet  for  print  drying  racks 

Sink — lead  lined 

Wratten  safe  light,  series  No.  3,  40-watt  Mazda  bulb 

Safe  lights 

Electric  convenience  outlets 

Electric  outlet  for  enlarger 

Electric  bright  light 

Electric  exhaust  fan 

Fresh  air  inlet   (light  trap) 

Foul  air  discharge  duet 

Cold  water  faucet 

Combination  hot  and  cold  water  faucet 

Variable  overflow  drain  pipe 

Removable  drain  board 

Sliding  enameled  developing  trays 

Towel  rack 

Light-tight  door  gasket 

Air  thermometer 

Coat  hook 


Light-tight  blind  for   exterior  window 

Storage  shelf  for  chemicals,   etc. 

Storage  space  for  solutions 

Trimming  board  and  cutter 

Tray  storage  racks 

Storage  space 

Equipment  and  supply  drawers — full  depth  of  work  bench 

Bench  top  and  back  b'oard  covered  with  acid  and  alkali  proof  Micarta  1/16"   thick 

witn  chromrum  trim 

Foul  air  outlet  grille 

Proposed  recessed  cabinet  for  books  and  film  storage 







Fig.  96    Elevation  showing  sink,  exhaust  fan,  safe  lights,  drying  racks,  etc. 

Fig.  97    Plan  of  Lee  Parsons  Davis'  model  darkroom. 

Stocking  the  Complete  Laboratory 

Naturally  one's  darkroom  equipment  and  supplies  will  be  determined 
by  individual  tastes  and  requirements.  Here  is  a  list  to  consider  when 
stocking  your  laboratory  with  everything-  but  the  "kitchen  stove". 

Developing1  tanks  for  film  .  .  .  developing  trays  for  paper  enlarge- 
ments .  .  .  enlarging  equipment  .  .  .  film  and  glass  slide  contact  printers 
.  .  .  illuminating  control  rheostat  for  use  with  photoflood  bulb  in  en- 
larger  .  .  .  paper  cutter  .  .  .  safety  lights  for  paper  and  films  .  .  . 
chemicals  and  chemical  weighing  scale  .  .  .  electric  agitator  for  film 
developing  tank  .  .  .  thermometer  .  .  .  cotton  and  viscose  sponges 
.  .  .  supply  of  bottles  for  keeping  solutions  .  .  .  supply  of  beakers  and 
graduates  for  mixing  and  measuring  solutions  .  .  .  small  electric  stove 
^for  heating  solutions  .  .  .  metal  clips  for  hanging  film  to  dry  .  .  .  de- 
veloping glass  drum  for  color  films  or  reversing  other  films  .  .  .  supply 
of  enlarging  paper  .  .  .  filing  boxes  for  negatives  which  must  be  kept 
free  from  dust  at  all  times  .  .  .  and  finally  a  small  corkboard  mounted 
on  the  wall  for  tacking  up  formulas  and  special  data  which  is  often  re- 
ferred to  such  as  weight  conversion  tables,  developing  times  at  various 
temperatures,  etc. 

A  Two  Room  Laboratory 

Now  let's  study  still  another  darkroom  or  laboratory  which  is  a 
little  more  elaborate  and  has  the  double  room  feature  with  a  small 
separate  nook  for  the  chemical  mixing  department.  This  darkroom 
was  designed  by  Clarence  Slifer  of  Hollywood,  California  and  de- 
scribed in  the  August  1934:  issue  of  the  American  Cinematographer. 
Mr.  Slifer  describes  his  laboratory  as  follows : 

In  keeping  with  the  progressiveness  that  is  so  apparent  in  Miniature 
Photography,  herewith  is  presented  a  plan  of  a  model  laboratory.  This 
room  in  which  photographic  processing  is  carried  on,  is  not  called  a  dark- 
room, simply  because  that  word  is  a  misnomer.  It  is  not  dark,  for  at  all 
times,  with  the  exceptions  of  when  loading  magazines  or  developing  tanks, 
there  is  an  abundance  of  light:  properly  filtered  light  for  printing  and 
daylight  for  other  operations. 

Removed  is  the  stigma  that  the  word  darkroom  has  implied.  This 
model  laboratory  is  not  a  poorly  ventilated  closet,  under  the  cellar  stairs, 
but  is  a  room  planned  for  comfort,  convenience,  and  practicability.  All  of 
which  are  conducive  to  better  photographic  work  and  the  full  enjoyment 
of  miniature  photography. 

From  the  plan,  it  will  be  noticed  the  room  is  divided  into  two  main 
divisions;  the  laboratory  proper  and  the  study.  The  laboratory,  to  take 
care  of  all  photographic  work  from  glossy  prints  to  the  advanced  pic- 
torial processes.  The  study,  to  serve  as  a  place  for  working  out  pho- 
tographic problems  or  as  a  place  where  you  may  argue  with  friends  about 
the  gammas,  the  paraphenylenes,  and  the  reticulations  of  photography, 
without  having  your  sanity  questioned  by  other  members  of  the  household 
or  being  relegated  to  that  esteemed  position  now  held  by  butterfly-chasing 

The  essential  features  of  the  model  laboratory  are: 

1.   A  shallow  wooden  sink  provided  with  removable  slats  for  tray  sup- 
ports.   Its  six-foot  length  easily  handles  three  trays  UTD  to  36"*20"  in 


Leica  Darkroom 

size.  Swing  faucets  practically  "cover"  the  entire  sink.  Above  the 
sink  are  shelves  for  stock  solutions,  etc.  Below  the  sink,  are  racks 
for  trays,  box  for  waste  and  space  for  miscellaneous  equipment.  In 
the  wall,  above  the  right  end  or  the  sink,  is  a  light-tight  ventilator. 
This  ventilator  withdraws  all  hypo  or  chemical  fumes  arising  from 
developing  or  toning  prints.  Also  at  this  end  of  the  sink,  is  a  light 
fixture  containing  a  day  light  bulb.  The  light  from  this  fixture  is 
concentrated  down  upon  the  hypo  or  toning  tray,  and  is  actuated  by  a 
foot  switch.  This  permits  examining  prints  for  tone  or  contrast  with- 
out drying  the  hands.  The  safe-light  used  for  observing  the  develop- 
ing of  prints,  has  two  degrees  of  brilliance:  dim  and  bright.  The 
bright  light  is  controlled  by  a  foot  switch  and  is  used  only  for  limited 
periods  of  print  examination.  For  cleanliness,  liquid  soap  and  paper 
towels  are  a  part  of  the  sink  equipment. 

2.  A  film  ^  developing  bench   especially  equipped   for  miniature   negative 
developing.     The  importance  of  agitation  in  small  film  processing-  is 
recognized  by  the   inclusion   of  an   electric   agitation  machine  in  the 
laboratory   equipment.     Also   provided   is  a  negative  viewing  box    (a 
white  light  behind  opal  glass).     Affixed  to  the  glass  are  gamma  films 
of  different  densities  for  use  in  judging  the  progress  of  development. 
An  ice  chest  for  cooling  solutions  may  be  placed  under  the  bench. 

3.  A  print  washing  machine  preferably  of  the  Kodak  rotating  type.    This 
provides  a  quick,  efficient,  and  thorough  means  of  washing  prints  with 
little  handling. 

Fig.  98  Plan  of  two 
room  laboratory  designed 
by  Clarence  Slifer 

•/CAlfr      1PODJ 


4.  A   drain-board  for  prints   after  they  have   been   removed   from   the 

5.  A  holder  for  paper  towels  and  a  shelf  for  the  radio   (the  companion 
in  the  laboratory).     Indicated  here,  is  a  stool,  as  much  printing  may 
he  carried  on  while  seated. 

6.  A  double,  indirect  safe-light  for  general  room  illumination. 

7.  A  long  cabinet  of  an   exaggerated   desk-like  appearance,  with   shelf 
or  cabinet  space  above.     Underneath  the  left  end  is  a  set  of  drawers 
for  keeping  Bromoil  brushes,  paints,  and  other  materials.     Space  is 
provided  for  leg-room  when  seated  before  the  portion  of  the  bench 
at  the  window.     Here  is  an  ideal  place  to  work  upon  Bromoils,  spot 
or  color  prints,  retouch  enlarged  negatives,  etc.    Underneath  the  right 
end  of  the  bench,  are  frames  with  stretched  cloth-net  for  laying  prints 
upon,  to  dry. 

8.  A  sliding  light-tight  shutter  for  the  window. 

9.  A  cabinet-bench  for  a  miniature  negative  enlarger  of  the  Leitz  Foco- 
mat  or  Valpy  type.    The  enlarger  is  controlled  by  a  foot  switch,  thus 
leaving  both  hands  free  for  "dodging".     This  freedom  is  further  en- 
hanced by  the  use  of  a  metronome  for  timing  prints  audibly,  during 
difficult  exposures.     At  other  times  a  large  electric  clock  serves  the 
purpose.    On  the  wall,  back  of  the  enlarger,  is  an  Illumination  Control 
Rheostat  for  use  with  a  Photo-flood  lamp,  when  enlarging  upon  chlo- 
ride (contact)  papers.    Light-tight  drawers  are  in  the  cabinet,  for  the 
storage  of  photographic  paper.    To  the  left  of  the  enlarger,  is  a  print 
trimmer.    To  facilitate  print  trimming,  the  edge  of  the  print  trimmer 
is  illuminated  by  a  light,  sunk  in  the  cabinet. 

10.  An  Il"xl4"  contact  printing  machine,  which  is  used  for  printing  en- 
larged negatives  and  also  strips  of  Leica  film,  for  proofs. 

11.  A  film  loading  and  negative  filing  desk. 

12  Chemical  closet,  for  chemical  storage  and  mixing.  In  the  lower  part 
of  the  cabinet,  is  a  bin  for  hypo  crystals  and  a  fixture  for  supporting 
a  five-gallon  bottle  of  distilled  water.  Due  to  its  location,  chemical 
dust  in  the  laboratory  is  eliminated. 

13.  Light-tight  entry  to  the  laboratory,  affording  easy  access  and  ventila- 
tion.   The  partitions  fold  back,  whenever  it  is  desirable. 

14.  Dry  mounting  press,  for  mounting  photographs. 

15.  Bookshelves,  for  those  indispensable  photographic  books   and  maga- 

16.  A  light-tight  film  drying  cabinet,   six  feet  high.     Air  is   drawn  in, 
through  silk  screens,  from  the  study,  thus  minimizing  the  nuisance  of 
dust.    The  cabinet  may  also  be  used  for  drying  hyper-sensitized  film. 

17.  A  cabinet  for  camera  equipment.     Upon  this  cabinet  is  an  easel  for 
holding  prints  to  be  admired  or  glared  at.     A  conventional,  picture- 
illumination  fixture  is  used  for  light. 

18.  A  Bromoil  transfer  press  and  a  cabinet  for  card  stock,  etc. 

19.  Desk-like  drawing  table  with  long  fixture  for  diffused  light  above. 

20.  Long,  comfortable  window  seat. 

The  plan  of  this  model  laboratory  is  based  upon  the  knowledge  gainec 
from  a  number  of  years'  experience  in  many  photographic  "darkrooms" 
So  turn  back  and  study  the  plan  over,  for  perhaps  you  may  find  some  ideas 
for  your  Ideal  Laboratory  for  Leica  Photography. 




After  the  Leica  negative  has  been  made  the  next  step  is  to  have 
it  printed,  either  by  contact  upon  paper  or  film,  or  by  direct  enlarge- 
ment. The  choice  in  printing  really  depends  upon  our  individual 
requirements.  Some  prefer  to  make  paper  contact  prints  of  all  their 
negatives  for  reference  purposes,  while  others  would  rather  make 
enlargements  direct.  In  order  to  reproduce  the  finest  qualities  in  a 
Leica  negative  it  is  necessary  to  either  make  positive  film  or  glass 
slides  for  projection  upon  a  screen  or  to  make  enlargements  upon 
some  of  the  various  printing  papers  now  available.  "We  will  discuss 
the  methods  for  enlarging  first. 

Making  positive  prints  from  Leica  negatives  offers  many  distinct 
advantages : 

1.  There  is  the  choice  of  many  fine  enlarging-  papers  which  may  be  secured 
in  various  surfaces  and  grades  of  contrast.     The  chapter  on  enlarging 
papers  will  give  complete  information  on  this  point. 

2.  Enlargements  may  be  shaded  or  dodged  during-  the  printing  in  order  to 
emphasize  or  hold  back  any  portion  of  the  picture.     For  example  an 
overexposed  sky  may  be  printed  longer  than  the  underexposed  fore- 

3.  The  unattractive  or  disturbing  parts  of  a  negative  may  easily  be  omitted 
to  improve  the  composition  of  the  finished  picture. 

4.  The  enlarging  easel  and  the  enlarger  housing*  may  be  tilted  for  correct- 
ing* the  perspective  in  a  picture.    This  feature  is  especially  valuable  when 
enlarging  architectural   pictures   which  have   been   taken   close  to   the 
subject  with  the  camera  pointed  slightly  upward  or  at  a  sharp  angle. 

5.  The  slow  printing  contact  or  chloride  papers  can  be  used  when  a  photo- 
flood  bulb  is  placed  in  the  enlarger. 

6.  Enlarging  screens,   gauze,  special  effect  filters,   and   other  accessories 
may  also  be  used  with  the  enlarger  for  securing  special  effects  in  en- 
largements to  please  the  various  individual  tastes. 

7.  The  Leica  enlargement  of  post  card  size  or  larg-er  produces  a  picture 
which  can  easily  be  studied  by  anyone. 

Selecting  the  Enlarging  Equipment 

Before  the  actual  enlargements  can  be  made  it  is  necessary  to 
select  the  proper  enlarging  equipment.  A  good  enlarger  will  last  a 
lifetime.  By  actually  enlarging  your  own  negatives  you  will  learn 


many  things  about  your  pictures.  You  will  have  a  keener  sense  of 
the  proper  composition,  a  better  judging  of  correct  exposures,  im- 
proper focusing  \vill  show  up  instantly,  and  even  when  you  are  making 
your  original  picture  you  may  have  in  mind  certain  enlarging  papers 
for  the  subjects  taken.  So  in  order  to  gain  these  advantages  let's 
become  more  familiar  with  the  actual  working  equipment  available. 

The  Valoy  Enlarger 

The  present  Valoy  enlarger  is  actually  the  outgrowth  of  the  former 
Filoy  and  F^lab  enlargers.    While  these  latter  enlargers  are  still  producing 
excellent eJargemeiat!  for  those  who   still  own  them,  the  present  Valoy 
enlarger  was  constructed  to  give  a  few  additional  conveniences  in  handling 
the  negatives.    This  enlarger  may  be  described  as  follows: 
1    Baseboard,  15%  x  18  inches  in  size,  for  holding  the  paper  easel  and 
the  metal  upright  bar  which  supports  the  enlarger  lamp  housing. 

2.  Upright  metal  bar,  l£  inches  in  diameter,  available  in  80cm  and  120cm 
lengths.     Electric  connecting  wire  passes   through  the  center  of  the 
metal  upright.     At  the  base  of  the  upright  iS>  a  grounding  connection 
marked  "E"  for  attaching  a  ground  wire  if  desired. 

3.  Lamp  housing  supported  by  an  extension  arm  which  clamps  around 
the  metal  upright  bar. 

4  Adjustable  lamp  base  for  centering  and  otherwise  moving  the  enlarging 
bulb  into  the  best  position  to  give  an  even  illumination  over  the  entire 
negative  area. 

5.  Removable  condenser  with  adjusting  lever  for  clamping  Leica  negative 
into  position  for  enlarging. 

6  Space  for  accommodating  various  masks  for  single  frame,  Leica  double 
frame,  3  x  4cm,  and  4  x  4cm  negatives.  Hinged  glass  negative  holders 
also  available  for  use  with  single  negatives  which  have  been  cut  from 
the  regular  rolls. 

7.  Focusing  lens  mount  will  accommodate  the  ^various  Leica  lenses.     The 
50mni  lenses  are  recommended  for  use  in  this  enlarger. 

8.  The  condenser  may  be  removed  for  cleaning  by  turning  the  clamping 
ring  inside  of  the  lamp  housing,  removing  the  spring,  and  then  lifting 
out  the  condenser.     It  is  a  good  plan  to  remove  this  condenser  fre- 
quently and  carefully  clean  the  surface  with  lens  tissue  or  a  clean 

9.  An  Intermediate  ventilating  ring  is   recommended  for  use  with  the 
Valoy  enlarger  when  a  photoflood  bulb  is  used. 

10.   A  small  snap  switch  is  attached  to  the  baseboard  of  the  enlarger  for 
making  the  exposures. 

The  Focomat  Enlarger 

The  Focomat  Enlarger  is  ver7  similar  to  the  Valoy  Enlarger  with 
the  exception  of  the  automatic  focusing  features.  The  lamp  housing, 
movable  condenser  and  method  of  inserting  the  film  in  the  Focomat 
Enlarger  is  just  the  same  as  in  the  Yaloy  Enlarger.  The  differences 
may  be  mentioned  as  follows : 



Fig.  99  Valoy  Enlarger, 
complete  with  easel,  mag- 
nifier, orange  filter  and 
negative  masking  carrier 

Fig.  100     Focoinat  Enlarger,  complete  with 
easel  and  orange  filter 

1.  As  shown  in  the  illustration  the  Focomat  Enlarger  has  two  extension 
arms  which  attach  the  lamp  housing  to  the  upright  pillar.    The  upper 
arm  holds  the  lamp  housing,  while  the  lower  arm  likewise  holds  the 
lamp  housing  in  a  vertical  position  and  at  the  same  time  makes  the 
changes  in  the  focus  of  the  lens. 

2.  The  Focomat  Enlarger  can  be  adapted  for  use  with  any  50mm  Leica 

3.  There  are  three  different  settings  on  the  focusing  ring  of  this  enlarger. 
These  settings  are  used  with  the  different  film  holders,  such  as,  the 
regular  holder  for  receiving  rolls  of  Leica  film,  and  also  the  glass  plate 
holder  which  holds  the  film  in  a  slightly  different  plane  for  enlarging. 

4.  A  magnification  scale  is  included. 

5.  On  the  upright  pillar  there  are  two  holes.     The  upper  one  is  for  use 
with  the  enlarger  when  the  paper  holding  easel  is  in  position.     The 
lower  hole  is  used  for  marking  the  position  of  the  bracket  on  the  lamp 
housing  when  the  easel  is  not  to  be  used. 

The  Focomat  Enlarger  is  focused  with  one  of  the  Leica  lenses  sat  the 
Leitz  Company  in  New  York  before  delivery.  Once  this  setting  has  been 
made,  there  is  no  need  for  making  a  change.  Any  of  the  50mm  Leica 
lenses  may  be  used  or  the  special  Varob  Enlarging  Lens  can  be  used.  The 


Varob  lens  is  really  recommended  because  this  lens  can  be  left  on  the 
enlarger  continually  and  it  will  not  be  necessary  to  use  the  lens  from  the 
Leica  Camera. 

Fig.  101  Focomat  Enlarger  which 
accommodates  all  negative  sizes  up 
to  2%  x  Sy2  inches. 

Fig.  102  Vanos  Enlarger 
for  use  with  all  negatives 
up  to  2%  x  3%  inches. 
Note  counterweight  for 
balancing  weight  of  en- 

Enlarger  Accessories 

There  are  various  accessories  for  use  with  the  Valoy  and  Foco- 
mat Enlargers.  Masking  plates  for  use  with  single  frame,  double  frame, 
3  x  4cm,  and  4  x  4cm  negatives  may  be  used  in  these  enlargers.  Glass  plate 
negative  holders  are  also  available  for  enlarging  single  negatives.  The 
2%  x  3%  Focomat  and  Vanos  Enlargers  accommodate  all  film  sizes  up  to 
their  maximum  areas.  Orange  niters  are  also  of  value  when  making  en- 
largements or  glass  lantern  slides.  A  special  attachment  ring  is  available 
for  fitting  to  the  Elmar  or  Hektor  50mm  lenses.  This  ring  permits  the 
operation  of  the  iris  diaphragm  by  turning  a  knurled  ring  with  a  special 
calibrated  scale  on  the  side.  In  this  way  it  is  very  easy  to  read  the  lens 
-stops  from  the  side  of  the  ring.  As  all  enlargements  should  be  made  with 
the  lens  closed  down  at  least  two  or  three  stops,  such  a  ring  is  recom- 
mended. Preliminary  focusing  is  done  with  the  lens  wide  open. 

The  Vanos  Enlarger 

The  Vanos  Enlarger  is  designed  for  enlargement  of  all  sizes  of  minia- 
ture camera  negatives.  This  enlarger  will  accommodate  all  films  from 
the  single  frame  size  of  35mm  film  to  2%  x  3%  inches.  Its  optical  system 
is  so  arranged  that  the  Leica  interchangeable  lenses  can  be  used  in  it.  As 
standard  equipment  a  95mm  lens  is  available.  The  focusing  bellows  is 
adjustable  for  use  with  other  interchangeable  Leica  lenses.  The  Vanos 
Enlarger  as  well  as  the  large  size  Focomat  Enlarger  have  stationary  con- 
densers. A  special  optically  flat  glass  sandwich  plate  is  used  for  holding 
Leica  films  or  cut  films  up  to  2%  x  3%  inches,  otherwise  the  method  of 
using  the  Vanos  Enlarger  is  practically  identical  with  that  of  the  Valoy 
or  the  small  Focomat  Enlarger. 



A  special  Offset  Arm  is  also  available  for  use  with  the  Valoy  and 
Focomat  Bnlargers.  This  Offset  Arm  is  of  special  value  when  making  "big 
enlargements  because  the  lamp  housing  is  extended  an  additional  6  inches 
away  from  the  upright  pillar.  As  the  Offset  Arm  contains  a  short  rod 
itself,  it  is  possible  to  raise  the  lamp  housing  of  the  enlarger  about  18 
inches  higher  than  the  top  of  the  regular  upright  bar  which  comes  with  the 
enlarger.  Even  when  making  huge  enlargements  up  to  2  or  3  feet  or 
greater,  this  Offset  Arm  can  be  used  very  successfully  in  the  horizontal 
position.  The  arm  may  be  moved  vertically  or  horizontally  by  loosening 
the  set  screw  and  turning  the  attachment  in  various  positions.  In  the 
horizontal  position  as  shown  in  the  illustration,  the  picture  may  be  pro- 
jected upon  a  wall  for  making  the  huge  enlargements. 

If  the  Leica  lens  is  used  without  the  Adjustable  Diaphragm  Ring,  the 
figures  engraved  on  the  lens  mount  represent  the  following  ratios: 

Relative  Aperture: 
Ratio  of  Exposure: 

1.9  (2.0)     2.5       3.2  (3.5)     4.5     6.3     9     12.5     18 
0.36  0.63     1  2        4        8     16        32 

Fig.  105  Diaphragm  King, 
available  for  Elmar  35mm 
and  50mm,  and"  for  Hektor 
50mm  lenses  when  these 
lenses  are  used  on  en- 

Fig.  103  Offset  arm  for 
making  great  enlarge- 

Making  the  Actual  Enlargements 

Now  let's  suppose  that  the  Valoy  Enlarger  has  been  selected  and 
we  are  ready  to  make  our  first  enlargements.  First,  check  up  on  the 
darkroom  equipment  and  make  certain  that  the  following  materials 
are  available: 

1.  The  Valoy  Enlarger. 

2.  Developer,  short  stop,  and  hypo  solutions  as  well  as  trays.     The 
trays  can  be  selected  for  the  size  of  enlargements  which  will  be 
made.    A  set  of  5  x  7  and  8  x  10  inch  trays  are  always  of  value. 

3.  Enlarging  paper.     (See  next  chapter  on  Enlarging  Papers). 

4.  Check  up  on  the  proper  safe-light  and  other  accessories  for  the 
darkroom  use.     (See  chapter  on  the  Leica  Darkroom). 


Montage  by  Barbara  Morgan         Photos  by  Henry  Kloss 

All  photographs  made  with  Summar  50mm  lens,   1/1000  second  at  f  :4.5 

Eastman  Super-X  ftlro  Note  reversible  prints  used  in  design 

After  all,  there  is  very  little  equipment  required  for  making 
Leica  enlargements.  You  can  easily  confiscate  the  kitchen  sink  and 
drain  board  for  this  work  after  the  windows  have  been  covered  with 
a  blanket  or  black  cloth.  The  darkroom  chapter  will  give  you  more 
complete  information  about  becoming  a  'bathtub  finisher. 

Before  placing  the  Leica  negative  into  position  in  the  Valoy  En- 
larger,  make  certain  that  there  are  no  dust  particles  clinging  to  the 
film.  If  there  are,  remove  them  with  a  soft  brush  or  with  a  clean 
lintless  linen  cloth.  The  movable  condenser  should  always  be  in- 
spected for  dust  or  dirt  particles.  These  points  are  very  essential 
because  small  dust  particles  may  spoil  an  otherwise  perfect  enlarge- 
ment if  they  are  not  removed  beforehand.  The  Negative  Viewer  and 
Marker  can  be  used  very  successfully  for  picking  out  the  best  nega- 
tives for  enlarging.  "With  this  attachment,  it  is  possible  to  make  a 
small  nick  in  the  edge  of  the  film.  Then,  while  working  in  the  dark- 
room, the  negatives  can  be  picked  out  very  quickly  by  running  a 
thumb  along  the  edge  of  the  film. 

When  the  correct  negative  has  been  selected,  insert  the  film  into 
the  negative  carrier  of  -the  enlarger  with  the  emulsion  side  down. 
Snap  on  the  light  and  move  the  film  so  that  it  appears  in  the  frame 
which  is  projected  down  onto  the  paper  holder.  This  can  be  done 
while  the  condenser  is  in  the  raised  position.  Next,  move  the  clamp- 
ing lever  forward  in  order  to  release  the  condenser  and  thus  clamp 
the  film  into  a  plane  position.  Now,  raise  or  lower  the  lamp  housing  and 
turn  the  focusing  mount,  into  which  the  Leica  lens  has  been  screwed, 
until  sharp  focus  has  been  secured  over  the  entire  picture  area. 

Some  Leica  workers  secure'  critical  focusing  by  placing  special 
negatives  with  sharp  line  drawings  in  the  enlarger  before  the  regular 
negative  to  be  enlarged  is  inserted.  Then,  when  perfect  focus  is  se- 
cured by  projecting  the  lined  negative  onto  the  enlarger  easel,  the 
focusing  negative  is  removed  and  replaced  by  the  regular  film  strip. 
A  black  over-exposed  frame  can  also  be  used  for  this  purpose  provid- 
ing a  few  fine  scratches  are  made  on  the  emulsion  side  of  the  film. 

A  hand  magnifier  or  reading  glass  can  also  be  used  for  viewing 
the  projected  image  on  the  enlarging  easel.  Sometimes  this  latter 
method  is  very  convenient  for  securing  critical  focus. 

The  enlarging  easel  should  be  set  for  the  proper  size  of  the  enlarg- 
iftg  Paper-  The  two  adjustable  masking  bands  can  be  moved  for 
making  the  proper  adjustments.  It  is  best  to  have  a  small  white 
margin  around  the  finished  enlargement.  This  white  margin  can  be 
varied  according  to  requirements. 



After  the  projected  negative  is  properly  focused  and  centered 
on  the  enlarging  easel,  you  are  now  ready  to  make  an  exposure  test. 
Select  a  small  strip  of  enlarging  paper  and  place  it  on  the  easel  with 
the  emulsion  side  up.  Stop  the  lens  down  to  one  or  two  diaphragm 
stops.  A  small  pencil  flash  light  may  be  used  to  make  the  adjustment 
of  the  lens  diaphragm.  This  flash  light  can  be  covered  with  a  piece  of 
red  paper.  With  the  proper  lens  stop  set  you  are  now  ready  to  snap 
on  the  switch  and  expose  the  test  strip.  Two  or  three  different  ex- 
posure times  should  he  made  on  this  test.  A  small  card  can  be  moved 
across  the  test  strip  at  one  or  two  second  intervals,  depending  upon 
the  speed  of  the  paper  and  also  the  density  of  the  negative.  With  a 
little  practise  it  is  very  easy  to  count  seconds  without  watching  a 
clock.  There  are  various  methods  used  for  counting.  For  example, 
seconds  can  be  counted  in  this  way:  Thousand  1 —  Thousand  2 — 
Thousand  3 — .  Or,  if  this  may  be  too  monotonous,  try  the  following : 
1  chimpanzee,  2  chimpanzee,  3  chimpanzee,  etc.  There  are  excellent 
darkroom  clocks  with  second  hand  dials  for  use  in  timing  negatives  on 
enlarging  papers. 

The  diaphragm  stops  on  the  enlarging  lens  can  be  more  easily 
seen  if  a  small  white  card  is  placed  just  below  the  lens  in  order  to 
throw  the  reflection  of  the  light  back  onto  the  lens.  The  card  can  be 
bent  in  such  a  way  that  the  light  will  even  be  thrown  around  to  one 
side  of  the  special  attachment  ring  in  case  it  is  used  for  adjusting  the 
diaphragm  stops. 

After  the  test  strip  has  been  exposed,  place  it  in  a  developer  and 
develop  for  a  full  time  of  iy2  t°  2  minutes  in  case  of  bromide  papers. 
If  the  slow  chloride  contact  paper  is  used,  the  developing  time  will 
probably  be  about  one-half  the  time  required  for  bromide  paper. 
After  the  test  strip  has  been  fully  developed,  rinse  it  in  the  fixing 
bath  for  a  few  seconds  and  then  turn  on  the  white  light  and  examine 
the  exposures.  The  correct  exposure  can  usually  be  determined  very 
quickly.  Now  place  a  full  size  sheet  of  enlarging  paper  in  the  en- 
larging easel  and  snap  on  the  light  for  the  required  length  of  time. 
Remove  the  paper  and  place  it  in  the  developing  tray.  After  proper 
development,  rinse  the  picture  in  the  acetic  acid  short  stop  which  is 
made  up  as  follows : 

Acetic  Acid  (28%) 1l/z  oz.  48  cc 

Water    32      oz.         1000  cc 

From  the  short  stop  the  print  is  placed  in  the  acid  fixing  solution  for 
about  15  minutes.  See  the  next  chapter  on  Printing  Papers  for  in- 
formation about  the  acid  fixing  solution. 


After  the  picture  has  been  thoroughly  fixed,  it  should  be  washed 
in  a  tray  in  running  water  for  at  least  one  hour  before  placing  out  to 
dry  on  blotters  or  in  the  special  blotter  roll  which  is  now  available. 

Estimating  Print  Density 

Some  people  have  a  very  easy  time  turning  out  excellent  prints  which 
embody  everything-  that  is  known  as  quality.  Others  have  a  hard  time 
making  good  prints.  It  is  true  that  some  people  have  a  gift  for  such 
work,  having  the  ability  to  put  quality  into  their  prints  by  instinct  or  intui- 
tion, but  even  the  average  person  who  lacks  that  spark  should  be  able  to 
turn  out  most  satisfactory  prints  after  once  getting  the  feel  of  making 

Let's  see  what  is  involved  in  the  process  of  producing  a  latent  image 
upon  a  sensitized  paper  and  subsequently  converting  that  latent  image 
into  a  real  image  in  terms  of  black  and  white  and  the  intermediate  tones 
of  these  two  colors. 

The  emulsion  of  the  paper  coats  the  surface  very  similarly  to  that  of 
a  coat  of  paint*  Paint  consists  of  a  vehicle,  which  is  usually  linseed  oil 
or  other  more  or  less  volatile  substance,  and  tiny  particles  of  pigments 
suspended  in  the  vehicle.  The  emulsion  of  the  sensitized  paper  consists 
of  gelatine,  the  vehicle  in  which  particles  or  grains  of  light-sensitive  sil- 
ver bromide,  chloride  or  a  mixture  of  both  are  suspended.  The  emulsion 
has  a  thickness.  This  thickness  may  vary  with  the  different  types  of 
papers.  There  are  particles  of  sensitive  silver  salts  that  are  near  the 
upper  surface  of  the  emulsion  and  some  that  are  joined  to  the  surface 
of  the  paper.  And  there  are  particles  of  these  salts  scattered  in  between. 
When  light  strikes  the  surface  of  the  paper,  after  passing  through  the 
negative,  it  strikes  the  sensitive  silver  salt  grains.  If  little  light  reached 
the  surface  of  the  emulsion,  only  those  silver  grains  become  affected  by  it 
that  are  nearest  the  surface.  The  more  light  that  reaches  a  certain  point 
of  the  paper,  the  deeper  it  penetrates  into  the  emulsion  and  the  more  par- 
ticles of  silver  salts  are  affected  by  it.  Obviously  a  certain  na|xamum 
amount  of  light  must  be  admitted  to  the  surface  of  the  paper  tC  affect 
the  lower  layers  of  silver  salts  imbedded  in  the  emulsion. 

After  exposure,  the  latent  image  produced  upon  the  emulsion  of  the 
paper  must  be  developed  through  conversion  of  the  silver  salts  into 
metallic  silver  grains.  When  the  print  is  immersed  in  the  developer  its 
chemicals  begin  to  react  with  the  silver  salts  in  the  emulsion  after  the 
water  of  the  developer  softens  the  dry  gelatine.  The  particles  of  developer 
gradually  penetrate  into  the  thickness  of  the  emulsion  until  they  reach 
all  the  way  through  it  to  the  paper  proper.  Obviously  a  certain  minimum 
of  time  must  elapse  between  the  time  when  the  uppermost  grains  of  silver 
are  developed  and  the  time  when  the  lowermost  grains  are  converted 
into  silver. 

This  is  the  reason  for  the  requirement  of  paper  to  be  developed  for 
a  minimum  time  before  withdrawing  it  from  the  developing  solution.  In 
most  instances  that  minimum  time  for  bromide  and  chlorobromide  is  set 
at  one  and  one-half  minutes.  That  is  the  minimum  time  of  development. 
If  after  the  printing  has  been  developed  for  one  and  a  half  minutes,  and 
not  less,  it  appears  weak  and  flat,  it  apparently  has  been  underexposed  and 
more  exposure  should  be  given.  If  it  appears  to' be  too  dense  it  has  been 
apparently  overexposed  and  the  subsequent  exposure  should  be  shortened. 



Longer  development  than  the  minimum  of  one  and  a  half  minutes  is 
frequently  indicated.  Some  prints  acquire  a  certain  tone  quality  through 
longer  development.  Thus  it  can  be  said  that  with  certain  developers 
for  instance  after  a  minute  and  a  half  development  almost  all  details 
of  the  picture  are  available  and  the  development  is  continued  for  another 
half  minute  with  very  little  apparent  change  taking  place  in  the  print. 
But  when  finished  and  dry  such  print  will  have  that  quality  and  richness 
which  we  always  look  for. 

An  excellent  and  frequently  overlooked  method  of  learning  how  to 
make  good  prints  consists  of  making  some  prints  on  lantern  slides  or  on 
positive  cut  film.  The  emulsion  of  lantern  slides  and  positive  cut  film  is 
similar  to  that  of  bromide  papers.  Lantern  slides  and  transparencies  made 
on  positive  cut  film  have  a  greater  brilliance  and  greater  latitude  than 
bromide  papers.  This  is  only  measurably  true.  Their  emulsions  being 
almost  the  same,  the  difference  of  quality  results  from  the  viewing  method 
employed,  slides  being  viewed  by  transmitted  light  while  bromide  prints 
are  viewed  by  reflected  light.  This  difference  will  become  quite  apparent 
when^one  will  visualize  a  cross-section  of  an  emulsion  similarly  exposed. 
Bromide  paper  emulsion  and  lantern  slide  or  transparency  emulsions  of  a 
similar  negative  would  show  under  great  magnification  that  the  densities 

Fig.  107    Reflections 

of  the  deposit  of  black  silver  grains  are  almost  identical  and  they  form 
terrace-like  recesses  or  slopes  ranging  from  blackness  merely  at  the  sur- 
face of  the  emulsion  to  total  blackness  of  the  entire  thickness  of  the 
emulsion.  It  is  easy  to  see  that  transmitted  light  penetrates  through  these 
layers  of  different  degrees  of  blackness  with  a  different  intensity,  thus 
forming  degrees  of  intensity  that  can  be  likened  to  shades  of  gray.  Light, 
however,  that  is  reflected  from  a  black  surface  backed  with  white  paper 
can  produce  only  a  very  limited  range  of  tones  of  gray  which  would  de- 
pend on  the  thickness  of  the  black. 

Thus  if  one  would  use  positive  cut  film  or  lantern  slide  stock  instead 
of  bromide  or  chlorobromide  papers  for  enlargements  or  portions  of  en- 
largements one  will  begin  to  evaluate  these  differences  of  the  thickness 
of  silver  deposits.  Lantern  slides  or  transparencies  must  be  viewed  by 
transmitted  light.  Viewing  them  in  a  developing  tray  will  produce  un- 
favorable, erroneous  results.  A  transparency  that  may  look  fully  devel- 
oped in  the  tray  will  look  flat  when  viewed  against  a  light  box.  And  one 
that  looks  totally  black  in  a  developing  tray  will  show  excellent  brilliance 
and  contrast  when  viewed  against  an  adequate  light  source.  A  dozen 
lantern  slides  or  pieces  of  positive  cut  film  would  be  an  excellent  invest- 
ment and  one  will  get  more  information  from  such  experiments  than  from 
a  whole  volume  written  on  the  subject.  That  is  the  only  way  to  get  the 
feel  of  the  matter  and  it  cannot  be  recommended  strongly  enough.  Later 
on,  after  having  made  a  number  of  prints  in  the  form  of  transparencies 
one  may  adopt  the  same  method  for  judging  prints:  when  they  are  devel- 
oped according  to  a  standardized  method  and  fixed,  view  them  against  some 
strong  source  of  white  light,  while  wet,  and  if  your  print  looks  good  that 
way,  it  certainly  will  be  good  when  dry  and  finished. 

Prints  should  be  wet  when  viewed  through  transmitted  light,  particu- 
larly those  made  on  double-weight  paper  which  may  require  a  stronger 
source  of  light  than  those  made  on  single-weight  paper. 

Incidentally  it  should  be  remembered  that  lantern  slides  and  cut  film 
transparencies  can  be  developed  in  the  same  developers  which  are  used  for 
developing  of  bromide  or  chlorobromide  papers. 

Printing  Control  During  Enlarging 

The  enlarging  of  a  negative  permits  much  greater  latitude  in 
the  actual  printing  control  as  compared  to  contact  printing.  During 
enlargement,  it  is  possible  to  introduce  soft  focus  lenses,  special  dif- 
fusion screens,  and  also  use  special  paper  masks  or  other  means  of 
dodging  the  picture  during  exposure.  While  contact  printing  permits 
very  little  variation  in  the  finished  print,  a  little  shading  is  about  all 
that  can  be  done  above  the  negative  during  exposure. 

Dodging  may  be  necessary  when  printing  a  negative  in  which  the 
sky  is  considerably  overexposed  while  the  foreground  may  be  normal 
or  even  underexposed.  The  correct  exposure  is  made  for  the  fore- 
ground and  then  a  cardboard  is  used  to  mask  out  the  foreground  while 
the  sky  is  given  a  few  additional  seconds  in  order  to  bring  out  the 
clouds  or  to  keep  the  sky  from  printing  white.  With  a  little  practice 



Fig.  108     Tea  Time 

Morgan  Heiskell 

and  ingenuity  the  operator  can  devise  various  methods  of  dodging  or 
shading.  For  example,  a  large  cardboard  can  be  cut  with  a  round 
hole  through  which  the  picture  may  be  projected  as  required  for 
bringing  out  certain  effects  in  the  print.  Also,  small  cardboard 
discs  can  be  attached  to  a  thin  wire  when  it  is  necessary  to  hold  back 
certain  portions  of  the  picture  during  exposure.  In  case  there  is  con- 
siderable dodging  to  be  done  on  a  print,  the  diaphragm  on  the  enlarg- 
ing lens  can  be  stopped  down  several  stops  more  in  order  to  give  a 
longer  working  time.  During  the  shading  process,  it  is  quite  essential 
to  keep  the  cardboard  moving  in  order  to  prevent  a  sharp  line  from  . 
appearing  where  different  exposures  are  made.  A  little  practise  will 
eliminate  this  trouble.  Many  enlargements  can  be  shaded  simply  by 
moving  the  hand  below  the  enlarging  lens  and  thus  blocking  out  any 
part  of  the  picture  which  may  be  necessary. 

Still  other  methods  of  control  are  possible  by  using  a  supple- 
mentary soft  focus  lens  in  front  of  the  enlarging  lens  or  a  thin  piece 
of  tulle  may  be  mounted  in  a  holder  and  moved  around  just  under  the 
lens  during  the  exposure.  Also,  special  effects  may  be  secured  by 
placing  screens  directly  over  the  enlarging  paper.  Sometimes  these 


screens  are  printed  on  glass  plates  in  order  to  give  a  small  space  be- 
tween the  screen  and  the  paper  and  thus  permit  a  slightly  softer 
result.  Still  another  method  of  obtaining  special  effects  on  the  en- 
largement is  by  using  a  clear  glass  plate  with  fine  sand  sprinkled 
around  the  plate  where  the  background  of  the  picture  is  to  be  held 
back  or  diffused.  For  example,  the  backgrounds  of  portraits  may  be 
printed  by  this  method. 

Although  many  people  like  to  use  these  special  methods  of  secur- 
ing certain  results,  the  ideal  way  is  to  make  the  enlargement  naturally 
without  diffusion  or  the  use  of  special  screens  which  only  give  a  false 
effect  in  an  attempt  to  imitate  etchings  and  lithographs.  It  is  not 
necessary  to  make  the  original  Leica  negative  through  a  diffusion  lens. 
Once  a  sharp  negative  is  available,  it  can  be  used  for  any  purpose 

Some  enlargements  may  be  greatly  improved  by  skilfully  using  an 
ordinary  flash  light  for  overexposing  certain  areas,  while  the  rest  of  the 
paper  is  covered.  In  doing  this,  the  orange  filter  is  moved  over  the  lens 
of  the  enlarger  in  order  to  prevent  exposure  on  the  paper.  However,  the 
projected  red  image  will  guide  you  in  flashing  the  light  over  the  areas 
which  are  to  be  darkened.  Thus  a  sky  may  be  made  almost  black  for  spe- 
cial effects,  or,  the  background  of  a  portrait  may  be  darkened  or  graded 
off.  Still  another  method  of  using  a  flash  light  is  for  making  a  small 
narrow  black  margin  around  the  printed  picture  while  it  is  still  in  posi- 
tion in  the  enlarging  easel.  To  do  this,  cut  a  sheet  of  cardboard  slightly 
smaller  than  the  final  picture  will  be.  This  cardboard  is  placed  over 
the  sensitized  paper  in  the  enlarging  easel.  By  moving  the  card  into  one 
corner  there  will  be  two  sides  left  with  a  margin  of  possibly  %  or  % 
of  an  inch.  Slowly  pass  the  flash  light  along  this  exposed  margin.  Then, 
push  the  card  into  the  opposite  corner  and  continue  around  the  other  two 
sides.  When  the  paper  is  developed,  the  image  as  well  as  the  black 
margin  will  appear  on  this  same  print. 

The  Use  of  Photoflood  Bulbs  in  the  Enlarger 

With  the  introduction  of  the  photoflood  bulbs,  it  is  now  possible  to  use 
greater  illumination  in  the  Leica  enlargers.  With  a  photoflood  bulb,  the 
slow  chloride  contact  papers  can  be  used  very  successfully.  As  these 
papers  require  considerably  longer  exposure  as  compared  to  bromide  papers, 
the  photoflood  illumination  is  perfect  for  making  the  exposures.  Very 
dense  negatives  can  likewise  be  used  with  the  higher  illumination  available 
from  photoflood  bulbs. 

A  rheostat  or  illumination  control  is  recommended  for  use  with  the 
photoflood  bulbs.  Such  controls  are  available  at  your  photographic  dealer. 
The  Leitz  Illumination  Control  is  made  for  one  photoflood  bulb  and  contains 
-seven  different  stops  for  varying  the  intensity  of  the  illumination.  Also, 
there  is  another  illumination  control  known  as  the  Variac  manufactured  by 
the  General  Radio  Company  in  Cambridge,  Mass.  The  Variac  Transformer 
can  be  used  for  delivering  voltages  between  zero  and  130  volts  from  the 
115  volt  circuit.  The  Variac  does  not  overheat  if  operated  continuously 


and  this  transformer  will  control  any  number  of  photoflood  lamps  tip  to 
four.  Such  a  method  of  controlling  the  photoflood  bulb  in  the  enlarger  is 
ideal  because  it  is  not  always  necessary  to  have  the  bulb  burning:  at  its 
brightest  intensity  for  making-  enlargements.  By  turning  down  the  volt- 
age and  using  the  bulb  at  less  illumination,  it  is  very  easy  to  do  all  the 
focusing  of  the  negative  and  thus  prolong  the  life  of  the  photoflood  bulb  as 
well.  The  Variac  Transformer  is  designed  for  use  on  alternating  current 
lines  only. 

It  should  be  noted  that  only  photoflood  bulbs  especially  designed  for 
enlarging  purposes  should  be  used.  Ordinary  photofloods  have  the  manu- 
facturer's emblem  at  the  tip  of  the  bulb  which  will  cast  an  objectionable 
shadow  upon  the  image.  This  emblem  cannot  be  removed  by  ordinary 
methods.  Special  enlarger  photofloods  are  made  with  the  manufacturer's 
emMem  placed  along  the  bulb's  neck.  Subsequently  a  photo  enlarger  bulb 
made  by  the  General  Electric  Co.  frosted  inside  and  out  for  better  diffusion 
is  known  as  the  200  watt,  105  to  120  volt  photo  enlarger  bulb. 

Occasionally  a  photoflood  bulb  may  break  or  crack  in  the  enlarger. 
Therefore,  it  is  a  good  plan  to  place  a  small  square  of  clear  glass  over  the 
movable  condenser  in  order  to  prevent  it  from  being  scratched  by  a  bulb 
which  may  possibly  break.  Also,  a  special  ventilating  ring  is  available  for 
placing  below  the  upper  half  of  the  lamp  housing.  This  ventilating  ring  will 
keep  the  enlarger  from  overheating  when  the  photoflood  bulb  is  burned  for 
any  length  of  time  for  making  the  longer  exposures. 

Frequently  it  is  possible  to  make  a  number  of  interesting"  pictures 
from  one  negative.  In  other  words,  a  negative  may  contain  two  or  three 
different  compositions  of  special  interest.  Individual  portraits  can  be 
selected  from  a  group  picture  by  greater  enlargement  of  the  negative. 
Naturally  when  negatives  are  to  be  enlarged  to  any  considerable  size, 
it  is  quite  essential  that  they  have  fine  grain  development  in  their  original 

Reduction  of  Leica  Negatives  by  Projection 

In  the  chapter  on  Making  Leica  Film  and  Glass  Positives,  there 
is  special  information  about  reducing  Leica  negatives,  or,  printing 
Leica  negatives  in  natural  size.  Considerable  interest  may  be  created 
by  preparing  a  series  of  Leica  enlargements  as  well  as  a  number  of 
Leica  reductions  from  the  normal  size  of  Leica  negative.  "When  making 
the  small  prints,  a  3,  6  or  even  9cm  Extension  Tube  may  be  placed  be- 
tween the  enlarger  and  the  enlarging  lens.  In  this  way  it  is  even  pos- 
sible to  reduce  a  Leica  picture  to  1/4  of  an  inch  in  diameter  if  neces- 
sary. Such  small  miniature  pictures  may  be  used  for  ring  or  locket 
settings  as  a  novelty. 

Micro  slides  can  be  successfully  enlarged  by  direct  projection  in 
one  of  the  Leica  Bnlargers.  Many  medical  and  professional  workers 
will  find  this  method  of  enlarging  micro  sections  of  special  value  for 
study  and  filing  purposes. 


Pig.  110     Gear  Cutting 

Suminar  50mm  lens,  5  seconds  at  f:12.5 
Perutz  Persenso  film 

I.  Luckman 

Contact  Printing 

It  is  also  possible  to  make  your  "contact"  prints  by  projection. 
Once  the  correct  setting  has  been  determined,  the  entire  strip  of  film 
can  easily  be  printed  within  a. few  minutes  after  a  few  test  strips  have 
been  made.  With  a  little  skill  it  is  also  possible  to  print  all  these 
test  strips  onto  one  large  sheet  of  paper  and  then  the  entire  sheet 
placed  in  the  developer.  This  method  is  recommended  for  filing  pur- 
poses especially.  The  individual  prints  can  be  numbered  and  the 
number  of  the  roll  as  well  as  any  other  data  may  be  placed  at  the  top 
of  the  sheet  of  paper.  If  desired,  a  master  negative  8^5  x  11  inches 
in  size  could  be  made  for  printing  the  numbers  as  well  as  the  outlines 
of  the  picture  spaces  before  the  contact  prints  are  made  on  the  sensi- 
tized paper.  For  this  purpose,  a  special  enlarging  easel  can  be  con- 
structed with  notches  or  guide  lines  and, the  easel  is  thus  moved 
from  frame  to  frame  as  the  prints  are  made. 

Actual  contact  printing  is  done  by  placing  the  Leica  negative  in  direct 
contact  with  the  sensitized  photographic  paper.  The  emulsion,  or  dull  side 
of  the  negative,  must  face  the  emulsion  side  of  the  paper.  In  other  words, 
contact  printing  is  really  natural  size  printing  where  the  printed  picture  is 


exactly  the  same  size  as  the  original  negative.  While  working  in  the  dark- 
room one  may  be  doubtful  about  the  emulsion  side  of  the  paper.  A  quick 
test  can  be  made  by  touching  the  tongue  at  one  corner  of  the  paper.  The 
side  which  feels  slightly  sticky  is  the  emulsion  side  which  is  also  slightly 

The  most  elementary  way  to  make  a  contact  print  is  to  place  a  strip 
of  photographic  paper,  emulsion  side  up,  on  a  smooth  surface.  Then,  place 
the  negative  face  down  on  the  paper  and  force  complete  contact  by  pressing 
a  glass  over  both.  This  setting  is  naturally  done  under  the  usual  darkroom 
safelight  for  paper.  The  white  light  is  turned  on  for  making  the  exposure 
on  the  contact  print.  The  enlarger  can  also  be  used  as  a  light  source  for 
this  purpose  very  readily.  In  case  the  enlarger  light  is  too  strong,  one  or 
two  sheets  of  tissue  paper  placed  in  the  film  plane  of  the  enlarger  may  be 
used  to  soften  the  illumination.  After  exposure  the  paper  is  developed. 

However,  most  workers  prefer  a  neat  printer  for  making  their  contact 
prints.  Such  a  printer  can  either  be  made  or  purchased.  The  Eldia,  Eldur, 
and  Laver  Printers  supplied  by  the  Leitz  Company  can  all  be  used  for 
making  paper  contact  prints  as  well  as  for  contact  printing  on  film  or  glass 
slides.  The  Willo  strip  printing  frame  made  by  Willoughby's  or  the  Agfa 
printer  can  also  be  used  for  printing  single  frame  and  double  frame 

The  chapter  on  Printing  Leica  Positives  gives  detailed  information 
about  using  the  Eldia,  Eldur  and  Laver  Printers.  These  printers  are  also 
illustrated  in  that  chapter.  In  the  Eldia  Printer,  the  paper  can  be  wound 
around  the  spool  with  the  negative.  Then,  the  empty  spool  on  the  opposite 
side  of  the  printer  is  turned  so  that  the  paper  and  film  both  advance  at 
the  same  time.  The  exposures  are  made  by  turning  on  the  enlarger  light 
or  any  other  strong  source  of  illumination  may  be  used.  This  same  method 
of  printing  can  likewise  be  used  in  the  Laver  Printer.  The  Eldur  Printer 
and  also  the  Glass  Slide  Printing  Attachment  for  the  Laver  Printer  can  be 
fitted  with  a  small  metal  pressure  plate  for  use  when  making  individual 
contact  prints  on  2  x  2  inch  paper  which  has  been  previously  cut  for  the 

A  number  of  Leica  users  have  even  made  a  contact  printer  by  taking 
two  pieces  of  plate  glass  cut  5  foot  strips  and  35mm  in  width,  or  the  exact 
size  of  the  film.  One  side  is  hinged  with  tape.  With  this  printer  it  is  very 
easy  to  place  a  negative  film  in  position  and  a  strip  of  unexposed  contact 
paper  over  the  film.  The  two  glass  plates  hold  both  in  perfect  contact 
during  the  exposure  when  the  white  light  is  turned  on.  Such  a  method 
is  very  rapid  although  it  is  necessary  to  make  a  normal  estimate  of  the 
exposure  for  the  entire  strip  or  film. 

Single  contact  prints  or  paper  strips  containing  4  or  5  exposures  can 
easily  be  developed  in  trays.  However,  when  longer  strips  of  3  or  5  feet 
are  to  be  developed,  it  is  necessary  to  use  a  special  developing  tray  with  a 
roller  weight  at  the  bottom  under  which  the  paper  strip  is  passed.  During 
development,  the  paper  strip  is  quickly  passed  back  and  forth  through  the 
developer  in  the  tray.  Such  developing  trays  may  be  secured  from  your 
photographic  dealer.  These  trays  can  also  be  used  for  developing  film 
strips  if  special  care  is  taken.  WJien  using  the  Azo  35mm  perforated  or 
unperforated  paper  which  may  be  secured  in  200  foot  rolls,  the  developing 
time  will  be  approximately  45  seconds,  when  using  the  D-72  Eastman 
Formula  at  a  dilution  of  one  part  of  developer  to  two  parts  of  water.  A 
different  developer  and  time  must  naturally  be  given  when  developing  nega- 
tive or  positive  films  in  this  type  of  tray. 

Still  another  method  of  developing  strip  paper  is  by  using  the  Correx 


or  Reelo  Developing-  Tanks.  The  paper  is  wound  into  the  reels  similar  to 
the  method  used  for  inserting  and  developing  film  negative  strips.  When 
development  is  complete,  the  reel  can  be  quickly  immersed  in  a  short  stop 
solution  for  a  few  seconds  and  then  placed  in  the  fixing  bath.  If  additional 
paper  strips  are  to  be  made,  the  paper  must  be  unwound  from  the  reel,  the 
reel  and  apron  are  then  thoroughly  washed  in  running  water  before  using 
again  for  development.  The  exposed  strip  of  paper  should  be  left  in  the 
fixing  solution  for  at  least  10  minutes. 

The  Agfa  Ansco  Company  supplies  the  fast  Brovira  paper  in  perforated 
35mm  width  for  contact  printing.  The  Azo  paper  supplied  by  the  Eastman 
Kodak  Company  as  well  as  the  Brovira  paper  may  be  secured  in  the 
various  degrees  of  contrast. 

After  the  contact  print  has  been  made,  the  single  prints  can  be 
mounted  for  quick  reference  for  indexing  purposes  on  individual 
cards  or  in  a  special  photo  album.  Special  mounting  masks  are  avail- 
able for  preparing  the  individual  contact  prints  for  filing.  There  is 
also  the  "Willoscope  available  for  viewing  single  contact  prints.  This 
little  device  has  a  magnifier  and  also  a  place  to  hold  the  single  contact 
print  for  viewing.  This  viewer  also  contains  a  space  for  the  contact 
prints  and  at  the  same  time  it  can  be  folded  in  a  very  small  space  and 
carried  in  the  pocket.  The  method  of  printing  or  mounting  the  indivi- 
dual pictures  on  a  sheet  8%  x  11  inches  in  size  may  be  of  great  value 
for  filing  purposes.  In  fact,  contact  prints  could  be  used  more  gen- 
erally than  they  are,  not  only  for  filing  purposes  and  keeping  track  of 
negatives,  but  also  for  making  attractive  contact  print  albums.  Con- 
tact prints  assembled  according  to  subjects  and  special  layouts  with  a 
few  captions  would  certainly  make  an  attractive  album.  It  is  sur- 
prising how  much  may  be  seen  even  in  a  small  contact  print. 

Mountain  Scene 

Elmar  35mm  I/SO  f  :5  Agfa  Superpan,  medium  yellow  filter. 

Ernst  Schwarz 



The  average  user  of  a  miniature  camera  is  having  relatively  little 
culty  in  turning  out  negatives  of  reasonable  quality.  Exposure 
ers  representing  but  a  fraction  of  the  first  cost  of  the  camera  have 
linated  the  guess-work  in  negative  making,  particularly  since 
iature  negatives  are  developed  uniformly  for  a  given  time  at  a 
d  temperature.  Nevertheless,  the  prints  of  most  workers  do  not 
n.  to  satisfy  them,  and  one  is  continually  asked,  "Why  don't  my 
its  have  lifer9 

The  answer  is  fundamental  to  miniature  photography.  In  order 
>btain  a  minimum  grain  size,  we  are  using  developers  of  very  low 
rer  and  are  developing  only  to  some  point  of  compromise  between 
mal  contrast  and  the  smallest  grain.  Photographers  using  larger 
atives  develop  in  solutions  of  considerable  power  and  carry  de- 
>pment  much  further.  Consequently,  the  contrast  of  their  nega- 
s  is  considerably  greater  than  that  of  ours.  Years  before  the 
ent  of  miniature  photography  paper  manufacturers  recognized 

need  for  papers  whose  inherent  contrast  corrected  for  mistakes 
levelopment  and  began  producing  papers  in  several  degrees  of 
trast  (soft,  medium,  hard,  etc.).  It  was  found  that  a  negative 
a  certain  contrast  had  become  the  accepted  standard  and  the 
mfacturers  designated  as  normal,  or  medium,  that  paper  which 
duced  the  most  pleasing  print  from  a  negative  of  this  quality. 
3e  the  formulas  recommended  by  manufacturers  in  every  paek- 

of  paper  are  based  on  this  average  negative,  we  must  consider 
negatives  in  the  class  which  manufacturers  call  weak  or  flat  nega- 
is  and  accordingly  must  use  the  contrasty  formulas  or  papers 
)mmended  for  such  negatives. 

Because  of  the  misleading  nature  of  the  term  normal  or  medium 
ipplied  to  papers,  most  workers  in  miniature  photography  believe 
b  they  should  not  have  to  use  any  other  paper  if  their  negatives 
e  been  correctly  exposed  and  developed.  Kather  should  the  be- 
ner,  if  he  must  follow  a  hard  and  fast  rule,  consider  the  use  of 


papers  of  greater  than  normal  contrast  as  being  the  standard  with, 
miniature  negatives.  In  those  cases  where  the  paper  is  furnished  in 
only  one  grade  the  contrast  formula  recommended  by  the  manufac- 
turer should  be  used.  If  this  rule  is  followed,  nine  out  of  every 
ten  negatives  which  at  present  are  unsatisfactory  will  become  valu- 
able additions  to  the  tyro's  file. 


Choice  of  Paper  Stocks  and  Surfaces 

Printing  papers  today  are  produced  in  so  many  surfaces  that  it 
would  be  impossible  to  give  any  comprehensive  list.  Different  manu- 
facturers use  widely  differing  designations  for  papers  of  very  similar 
surfaces,  so  that  the  only  satisfactory  way  of  choosing  some  special 
surface  is  through  an  inspection  of  samples.  If  the  prints  are  to  be 
reproduced  they  should  be  made  on  glossy  paper  and  ferrotyped 
unless  the  reproduction  is  to  be  considerably  smaller  than  the  original, 
in  which  case  semi-matt  papers  are  quite  suitable.  One  of  the  most 
beautiful  surfaces  is  obtained  by  using  a  matt  or  rough  matt  paper 
and  waxing  the  finished  print  with  a  waxing  solution  obtainable  in 
any  photo  supply  house. 

The  paper  stocks  most  commonly  used  are  white,  cream  and  buff; 
the  most  common  weights  being  the  single  weight,  generally  used  for 
contact  work,  and  the  double  weight  or  light  card,  usually  associated 
with  enlargements.  Prints  which  are  not  to  be  mounted  in  albums 
or  on  regular  mounts  are  much  more  satisfactory  on  double  weight 
stock,  while  prints  for  mounting,  particularly  in  albums,  are  best 
made  on  single  weight  stock.  No  hard  and  fast  rule,  however,  can 
be  attempted.  "With,  regard  to  the  color  of  the  stock  itself,  it  should 
be  remembered  that  black  and  white  prints  are  not  satisfactory  on 
buff  tinted  mounts,  nor  are  buff  tinted  stocks  satisfactory  on  gray 
mounts;  white,  however,  is  satisfactory  with  almost  any  stock. 

Tone  Gradation 

It  is  impossible  to  reproduce  on  paper  every  gradation  of  gray 
available  in  the  negative.  This  holds  true  of  contact  printing  as  well 
as  enlarging.  Sensitized  paper  has  a  much  shorter  scale  than  nega- 
tive material.  The  reason  for  this  is  the  fact  that  a  picture  is  seen 
on  paper  by  reflected  light  while  a  negative  is  examined  by  trans- 
mitted light.  The  white  of  the  paper  will  not  reflect  more  than  50 
per  cent  of  the  light  falling  on  it  while  the  blackest  part  of  the  print 
will  still  reflect  at  least  2  per  cent  of  the  light  leaving  a  difference  in 
tone  of  perhaps  25  to  1  as  compared  with  60  to  1  in  the  negative,  since 
the  densest  part  of  a  negative  may  only  transmit  one-sixtieth  of 


first  learn  to  make  excellent  pictures  with  the  fundamental  process 
of  photography. 

Generally  the  tone  gradation  scale  is  shortest  in  fast  projection 
papers  and  is  longest  in  slow  papers.  It  is  claimed  that  the  longest 
scale  range  can  be  obtained  in  contact  or  so-called  chloride  papers. 
Contact  papers  are  available  in  as  many  as  six  grades  of  contrast 
while  projection  papers  only  in  two  or  three.  Thus  the  choice  of  a 
proper  degree  of  contrast  in  contact  paper  will  enable  one  to  obtain 
sometimes  a  better  print  on  contact  paper  than  on  projection  paper, 
provided  a  suitably  strong  light  is  available.  Although  I  have  my- 
self recommended  the  use  of  contrast  grades  of  paper  at  the  begin- 
ning of  this  chapter  and  again  here,  it  must  be  remembered  that  this 
is  only  for  beginners.  Normal  and  soft  grades  of  paper  produce 
beautiful  middle  tones  even  in  the  contrast  developers  recommended 
by  the  makers.  Contrast,  hard,  vigorous  papers  etc.  have  not  as 
yet  been  perfected  to  the  point  where  they  can  produce  the  full 
tone  scale  of  a  medium  grade  paper.  The  more  advanced  worker 
has  found  other  means  of  building  up  the  contrast,  either  in  develop- 
ment of  the  negative  or  in  later  steps  such  as  the  enlarged  negative 
processes.  However  the  beginner  will  get  very  acceptable  prints  by 
following  the  simple  process  of  using  the  contrast  grades  of  paper  or 
the  contrast  developers. 

Fast  Projection  Papers 

Fast  projection  papers  are  commonly  known  as  bromide  papers  because 
silver  bromide  is  the  sensitive  agent  in  their  emulsions,  in  fact,  the  emulsion 
is  very  similar  to  that  of  slower  plates  and  films.  Most  of  these  papers  are 
made  in  several  degrees  of  contrast  as  well  as  a  variety  of  surfaces  and 
stocks  as  mentioned  above.  Some  idea  of  the  papers  commonly  used,  which 
fall  in  this  class,  can  be  obtained  from  the  following  list : 

Brovira  produced  by  the  Agf  a~Ansco  Company 
Velour  Black  Defender  Company 

PMC  Bromide  Eastman  Kodak  Company 

Novabrom  Gevaert  Company 

Press  Bromide  Haloid  Company 

Ilford  Bromide  Ilford  Ltd. 

Wellington  Bromide 

Wellington  &  Ward  Ltd. 

Slow  Projection  Papers 

Slow  projection  papers  are  known  as  chloro-bromide  papers  because 
their  emulsions  are  made  up  of  both  chloride  and  bromide  of  silver.  Be- 
cause of  the  presence  of  silver  bromide  these  papers  are  considerably  faster 
than  ordinary  contact  papers  whose  emulsion  is  made  up  entirely  of  silver 
chloride;  they  are  therefore  suitable  for  enlarging,  the  exposure  in  gen- 
eral being  approximately  four  times  that  necessary  for  a  regular  bromide 
paper.  The  long  range  of  tones  which  can  be  obtained  with,  these  papers  is 
making  them  very  popular  for  portrait  and  pictorial  work  as  is  also  their 


Enlarging  Papers 

moderate  speed  which  makes  them  available  both  for  direct  enlargements 
and  for  contact  prints  from  paper  negatives.  The  papers  most  commonly 
used,  which  fall  in  this  class,  are  as  follows : 

produced  by  the  Agfa-Ansco  Company 

"          "  "  Dassonville  Company 

"          "  "  Defender  Company 

"          "  "  Eastman  Kodak  Company 

tt  cc  tc  <t  it  (( 

"          "  "  Gevaert  Company 

"  "  Haloid  Company 

"  "  Ilford  Ltd. 

«  «  Wellington  &  Ward  Ltd. 


Charcoal  Black 


Illustrators'  Special 






Contact  Papers 

Contact  papers  are  often  called  chloride  papers  because  they  depend 
for  their  sensitivity  on  chloride  of  silver  alone.  Being  very  slow  they  were 
seldom  used  for  enlargements  until  the  development  of  the  photo-flood  lamp 
and  its  use  in  miniature  enlargers.  Proper  selection  of  the  contrast  of  the 
paper  will  reward  the  user  with  very  pleasing  results.  There  are  so  many 
contact  papers  available  on  the  market  today  that  any  attempt  to  list  them 
would  be  wholly  inadequate.  However,  contact  papers  manufactured  by  the 
firms  making  the  projection  papers  listed  above  are  as  follows: 



Azo  &  Velox 


Industro  &  Nomis 


produced  by  the  Agfa-Ansco  Company 
"          "      "    Defender  Company 
"          "      "    Eastman  Kodak  Company 
"          "      "    Gevaert  Company 
"      "    Haloid  Company 
"      "    Wellington  &  Ward  Ltd. 

Wickie  and  Suzanne 

Siaxnmar    50mm,    f:6.3  Peromnia   Film. 

Ed.  Schaefer 


The  following  tables  give  the  formulas  recommended  by  the 
paper  manufacturers  for  their  papers  most  commonly  used  in  en- 
larging. The  formulas  have  been  grouped  in  three  classes,  soft, 
medium  and  hard,  but  it  should  be  remembered,  however,  that  the 
hard  formulas  are  the  ones  which  should  be  used  with  papers  pro- 
duced in  only  one  degree  of  contrast  as  their  natural  contrast  falls 
in  the  class  of  medium  papers. 


Metol    80 

Sod.    Sulphite    438 

Hydroquinone     24 

Sod.  Carbonate   328 

Pot.    Bromide    15 

Water  to  make 

Grains  Grams 




Grains  Grams 





Avd. — 32  Ounces 




Grains  Grams 





1.4  lH- 

Metric— 1000  cc 

Grains  Grams 






Novabrom  really  suggest  using  any  mixture  between  their  softest 
and  hardest  formulas  to  obtain  the  particular  contrast  required. 

Grains  Gram 
48          3.4 





D7S  Artura  D52  Haloid  V.B. 

Grains- Grams  Grains  Grams    Grains  Grams    Grains  Grams    Grains  Grams    Grains  Gram! 





13        1.0 
193      14.0 
32        2.3 
365      27.0 
4        0.3 
Avd.—  32  Ounces 




11        0.8 
164      12.0 
45        3.2 
109        7.7 
11        0.8 
Metric—  1000 





Sod.  Sulphite  
"Hydroquinone  .  .  . 
Sod.  Carbonate.. 
Pot.  Bromide  
Water  to  make 

,  131 
.     35 
,  197 
,       6 



Grains  Grams 



Grains  Grams 

Grains  Grams 


Sod.  Sulphite  .. 
Hx^lroquinone  . . 
Sod.   Carbonate 
Pot.    Bromide    . 
Water  to  make 








Grains  Grains 



Avd.  —  32  Ounces 













Metric  —  1000  cc 






Grains  Grams 











Grains  Grams 
Metol  ..................     21          1.5 

Sod.   Sulphite  ....  ......  350        25.0 

Hydroquinone    .........     80         5.7 

Sod.  Carbonate  ........  525        37.0 

Pot.  Bromide  ..........    15         1.1 


Grains  Grams 

24  1.7 

328  23.0 

83  5.9 

219  15.0 

31  2.2 

Grains  Grams 

Avd.—  32  Ounces 


Grains  Grams 

13          1.0             14  1.0 

277        20.0          1094  80.0 

117          8.3            130  9.3 

217        15.0            360  25.0 

25          1.8             70  5.0 

Metric — 1000  cc 


Water  to  make 

*D11  is  for  positive  film  and  is  shown  to  indicate  the  high   sulphite   content  required   for  fih 
processing  as  compared  to  paper.  ,  *wuw«su   lor  nil 

NvBr-~Novabrom.          GVA-Gevalux.          V.B.-Velour   Black.          DsV.—Dassonville. 

Several  two-solution  developers  could  be  recommended  for  use 
with  papers  produced  in  only  one  degree  of  contrast.  The  purpose 
of  separating  the  developer  into  two  stock  solutions  is  to  permit  the 
contrast  of  the  developer  to  be  altered  by  altering  the  proportion  of 
the  two  stock  solutions.  It  will  be  noticed  in  the  previous  tables  that 
Eastman's  D64  formula  approximates  the  average  in  each  contrast 


Enlarging  Papers 

To  those  workers  who  may  object  to  a  formula  requiring  two  or 
three  stock  solutions,  a  universal  developer  formula  is  offered  with 
the  full  confidence  that  it  will  prove  invaluable  as  an  all-round 
developer  for  everything  except  negative  films.  This  formula  is 
comparatively  simple  to  prepare,  keeps  almost  indefinitely,  produces 
beautiful  tones  on  almost  any  kind  of  paper,  can  be  used  successfully 
not  only  for  contact  papers  and  projection  papers  but  also  for  lantern 
slides,  positive  films,  transparencies,  etc.  This  formula  approximates 
Eastman's  D52,  which  our  table  indicates  as  of  medium  contrast. 

Universal  Developer 

Water  (at  125°  F) 


Sod.   Sulphite    (dry) 


*  Sod.  Carbonate    (dry) 
Pot.  Bromide 

Methyl  Alcohol  (wood  alcohol) 
Cold  Water  to  make 

*  If  Monohydrated  Sod. 
Carbonate   is  used 

16  ounces 
75  grains 

2l/2  ounces 
300  grains 

Zl/z  ounces 
75  grains 

4%  ounces 
32  ounces 

500  cc 

5  grams 
75  grams 
20  grams 
105  grams 
5  grams 
150  cc 
1  liter 

4  oz.,  10  grains     120  grams 

Dissolve  above  chemicals  in  the  order  given.  It  will  be  found  that  the 
Hydroquinone  and  Carbonate  will  not  dissolve  completely  until  after  the 
wood  alcohol  is  added.  It  will  be  found  helpful  to  mix  the  alcohol  with  an 
equal  amount  of  cold  water  before  adding-  it  to  the  solution.  Add  alcohol  and 
water  mixture  slowly  while  stirring.  The  solution  will  gradually  clear. 
Filter  it  into  an  amber  glass  bottle.  It  is  ready  to  use  as  soon  as  cool. 

This  developer  works  best  at  approximately  70°  F.  It  should  be  diluted 
as  follows: 

Stock  Solution        Water 

For  Bromide  papers,  lantern  slides,  positive  film, 

transparencies   1  part  6  parts 

For  Chloro  Bromide  papers  (slow  projection) 1  part  4,  5  or  6  parts 

For  Contact  papers . 1  part  3  parts 

Many  photographers  like  the  rich  blacks  obtainable  with  an  amidol 
formula  such  as  the  following: 

Amidol  Developer 

Pot.  Br. 

32  oz. 
328  grains 
10-30  grains 
50  grains 

1      liter 
23.4  grams 
3.6  grams 
0.7  to  2.1  grams 

The  chief  difficulty  with  amidol  is  the  staining  of  fingers  and  the  necessity 
•of  preparing  fresh  developer  each  time  it  is  used.  The  developer  rapidly 
oxidizes  with  use,  becoming  discolored  and  unserviceable  within  an  hour  or 
so.  The  addition  of  50  grains  (3.5  grams)  of  Pot.  Meta-bisulphite  to  the 
Sulphite  solution  when  mixing  the  developer  will  considerably  lengthen  its 


useful  life,  particularly  if  the  sulphite  and  meta-bisulphite  are  boiled  to- 
gether for  several  minutes.  In  using  this  developer,  papers  manufactured 
in  several  different  contrasts  must  be  used,  inasmuch  as  little  change  can  be 
effected  by  altering  the  developer. 

The  staining  of  the  fingers  will  not  occur  if  the  precaution  of  rinsing 
the  fingers  every  time  they  have  been  in  solution  is  observed.  This  should  be 
done  in  all  developing  to  avoid  carrying  back  into  the  developer  the  oxidized 
solution  left  on  the  fingers. 

Altering  Developers 

The  amount  of  bromide  given  in  the  stock  solutions  is  the  mini- 
mum amount  required  to  keep  the  highlights  clear;  it  may  be  in- 
creased from  this  point,  increasing  the  warmth  of  tone,  up  to  the 
degree  of  warmth  manifested  in  an  olive  brown  tone.  The  maximum 
is  about  40  to  50  grams  per  32  ounces  of  ready  to  use  developer. 

Aside  from  modifying  the  bromide  content  of  developers,  varia- 
tions can  be  obtained  by  adjusting  the  proportion  of  metol,  hydro- 
quinone  and  carbonate  in  any  MQ  developer.  For  instance,  to  gain 
additional  contrast,  the  Hydroquinone,  Potassium  Bromide  and  Car- 
bonate can  be  increased  in  equal  proportion.  The  increase  in  bro- 
mide is  necessary  to  prevent  too  vigorous  action  and  will  not  appre- 
ciably alter  the  color  of  the  print,  the  additional  carbonate  offsetting 
this  tendency  as  well  as  increasing  the  developing  action.  For  softer 
results  the  metol  can  be  increased  considerably  if  the  hydroquinone 
is  decreased  proportionately  and,  if  extreme  softness  is  required,  the 
carbonate  can  also  be  decreased.  Decreasing  the  carbonate  slows  up 
development  and  gives  olive  tones,  whereas  increasing  the  carbonate 
increases  the  speed  of  development  and  gives  very  black  tones. 

So  much  for  developers.  Each  package  of  paper  and  every  maga- 
zine offers  some  variation  of  the  foregoing  with  sufficient  instructions 
to  cover  their  preparation  and  use.  Because  of  the  complex  nature 
of  the  developing  process  and  the  uncertainty  of  results,  if  different 
developers  are  used,  it  is  advisable  for  the  beginner  to  definitely 
choose  one  formula  and  stick  to  it  until  he  has  learned  to  produce 
consistently  satisfactory  results  with  it,  making  only  such  modifica- 
tions as  seem  necessary  to  obtain  greater  or  less  contrast  or  colder 
or  warmer  tones. 


This  brings  us  to  the  most  difficult  problem  of  all,  determining 
the  correct  exposure  for  the  print. 

It  should  be  borne  in  mind  that  the  final  print  density  is  the 
result  of  both  exposure  and  development,  thus  if  a-  test  were  made 
and  the  test  strip  developed  for  say  two  minutes,  the  subsequently 
correctly  exposed  print  should  also  be  developed  for  two  minutes. 


Enlarging  Papers 

However,  having  determined  the  exposure  by  these  means,  it  is 
still  necessary  to  make  one  or  more  tests  before  the  final  exposure  will 
be  decided  upon.  Most  of  us  in  making  test  prints  attempt  to  conserve 
our  paper  by  using  a  small  strip,  and  find  it  extremely  difficult  to 
decide  from  an  inspection  of  the  strip  whether  or  not  the  exposure 
really  was  correct.  It  has  been  my  experience  that  if  the  test  in- 
cludes the  whole  picture  it  could  be  extremely  small  (same  size  as 
the  negative)  and  still  a  very  good  estimate  of  the  necessary  varia- 
tion from  the  exposure  given  could  be  made;  far  better  than  from  a 
test  strip  the  same  size  or  larger  comprising  but  a  small  portion  of 
an  8  x  10  enlargement. 

Therefore,  I  prefer  to  make  my  test  prints  2x3  inches  in  size 
using  the  entire  negative.  Prom  this  slight  enlargement  (2x)  a 
quite  critical  examination  can  be  made  in  bright  light  after  the 
print  has  fixed  for  a  minute  or  two.  Not  only  can  the  correct  ex- 
posure be  determined  but  the  picture  itself  can  be  studied.  By  cut- 
ting an  8x10  sheet  into  four -strips  each  two  inches  wide  a  total  of 
twelve  2x3  test  prints  can  be  made  with  very  little  waste  of  paper. 

All  tests  for  an  evening  7s  work  are  made  at  one  time  and  a 
record  of  the  correct  exposures  kept.  Sufficient  fresh  developer  must 
be  used  so  that  it  will  not  deteriorate  appreciably.  The  correct 
exposure  for  the  final  print  is  then  determined  by  multiplying  the 
correct  exposure  for  the  test  print  by  the  necessary  factor  to  com- 
pensate for  the  increased  enlargement,  as  given  in  the  table  below : 

Exposure  Factors  at  Various  Magnifications 

Size  of  Enlarged                                   MULTIPLYING  FACTOR 

Image  of  Full  Negative 

if  original  test  print  was: 

(Neg.  1x1%  in.) 

1x1%  in. 

2x3  in. 

#JL£%  in. 

1x1%    inches 












































12x18       * 

















Another  table  which  proved  very  helpful  is  that  of  squares  of 
certain  basic  stop  values: 

f:  Values:  1.9         2*2         3.2         3.5        4.5         5.6         6.3  8  9         12.5         18         25 

f :  Values 

Squared:  3.6         4.8       10.2       12.2       20.3       31.4       39.7         64         81       156          324       625 


First  Stop 

Used—  f 


Proposed  Stop  —  f: 











18    25 












90   170 












30    50 












8    16 












2     4 












1     2 












1/2   1 

A  few  examples  I  believe  will  suffice  to  show  the  use  of  these 

First,  supposing  we  have  made  a  test  print  using  the  full  nega- 
tive enlarging  it  to  3x4%  inches.  The  correct  exposure  was  10 
seconds  at  f  :6.3.  Our  final  enlargement  is  to  be  11x14  losing  only 
a  small  portion  of  the  negative  at  each  end;  i.e.,  the  enlarged  image 
on  the  easel  would  measure  11x16%  inches  from  a  1x1*4  inch  nega- 
tive but  we  will  use  only  an  area  11x14  in  size. 

Consulting  our  first  table  we  find  that  the  exposure  should  be 
9  times  that  required  for  one  test  print  or  90  seconds. 

Consulting  the  second  table  we  find  that  if  an  exposure  at  f  :4.5 
is  made  it  need  be  only  %  that  at  f  :6.3,  so  we  can  open  our  lens  to 
f  :4J5  and  expose  45  seconds. 

Similarly  if  we  have  made  an  exposure  of  30  seconds  at  f  :6.3 
and  we  wish  to  double  the  exposure  without  increasing  the  time,  we 
find  from  the  second  table  that  f  :4.5  requires  %  the  exposure  of 
f:6.3,  so  we  open  to  f  :4.5  and  use  the  30  second  exposure,  getting 
the  same  result  as  60  seconds  at  f  :6.3  would  give. 

One  other  problem  frequently  occurring  is  that  when  we  have 
made  an  excellent  print  8x10  in  size  we  wish  to  repeat  it  on  11x14 
without  wasting  paper. 

Consulting  our  first  table  we  find  that  an  8x12  print  requires 
20  times  the  exposure  of  a  1x1%  and  that  an  11x16%  requires  36 
times  the  exposure  of  a  1x1%.  The  11x16%  inch  print  would  then 
require  36/20  or  9/5  the  time  required  for  the  8x12.  An  exposure 
double  the  exposure  given  the  8x12  would  be  close  enough.  This 
ratio  will  hold  true  regardless  of  the  amount  of  the  negative  used 
providing  the  larger  print  includes  the  same  proportion  of  the 
negative  as  the  smaller  print  did. 


Ruth  Henry  M.  Lester 

Elmar  90mm  lens,  %  second  at  f:6.3.     J)u  Pont  Superior  Film,  2  Pbotofloods 


Comparative  Speed  of  Yarious  Projection  Papers 

Another  bit  of  information  which  each  worker  must  determine 
for  himself,  but  which  is  invaluable,  is  the  relative  exposure  required 
for  each  brand  of  paper  as  compared  with  any  others  he  may  use. 
This  is  particularly  desirable  if  expensive  papers  are  being  used,  all 
preliminary  work  being  done  on  the  less  expensive  paper  and  the 
final  print  being  made  at  considerable  saving. 

Figures  opposite  each  paper  stand  for  UNITS  of  Exposure  Time. 

(UNITS:  seconds,  minutes  or  counts.) 

These  data  are  approximate  only  and  should  be  used  with  caution  as 
papers  vary  greatly  in  their  sensitivity  to  light: 

Agfa  Brovira  Gevaert  Novabrom 

Soft    1  Vigorous    7 

Medium     l1^  Normal    3 

Hard 3  Extra   Vigorous    8 

Extra  Hard    6  Gevaert  Gevalux  15 

Dassonville     1%  Eastman  Kodak 

Defender  Velour  P.M.C.  Normal    1 

Black  Soft    2  «        Medium    2 

"      Medium   3  «        Contrast    3 

"  "         Hard    5  News   Bromide   Soft    1 

"      Hard    6  «            «          Medium    ..     1% 

Veltura    25  «            «          Contrast..      2% 

Gevaert  Novabrom  Vitava    Projection    10 

Extra  Soft   2  Illustrators'  Special  20 

Soft    2%  Vitava  Opal    20 

It  should  be  borne  in  mind  that  there  is  a  definite  relationship 
between  the  exposure  time  given  a  print  and  the  time  of  develop- 
ment required  to  bring  out  as  many  details  of  the  negative  as  possible. 
Most  of  the  developers  used  for  papers  are  so  compounded  as'  to 
produce  a  fully  developed  image  in  one  and  a  half  to  two  minutes. 
Prints  developed  for  less  than  that  will  not  show  all  details,  while 
those  developed  for  longer  are  apt  to  appear  flat.  However,  just  as 
in  the  case  of  negatives,  a  certain  amount  of  latitude  is  available  in 
some  papers,  permitting  longer  exposures  and  shorter  development 
or  shorter  exposures  with  longer  development.  This  latitude  will 
enable  the  worker,  with  skillful  handling,  to  obtain  a  variety  of 
results  from  one  paper.  If  the  negative  is  very  dense  and  contrasty, 
a  softer  print  with  more  details  will  result  from  longer  exposure 


Enlarging  Papers 

and  shorter  development,  while  a  soft  and  flat  negative  will  yield  a 
snappier  print  with  underexposure  and  longer  development. 

Definite  knowledge  of  how  to  obtain  these  results  must  be  left 
to  the  worker  himself,  who  will  fully  succeed  in  the  proper  control 
of  Ms  paper  and  developer  provided  lie  will  select  one  paper,  one 
developer  and  learn  all  there  is  to  know  about  both. 

Short  Stop 

After  the  print  has  been  fully  developed  it  should  be  immersed  for  a 
few  seconds  (from  5  to  10)  in  a  so-called  short-stop  bath.  This  bath  is 
indicated  for  two  reasons.  It  instantly  stops  the  developing-  processes  of  the 
print,  and  it  neutralizes  the  alkalinity  of  the  developer,  preventing  the 
carrying  over  of  traces  of  developer  into  the  acid  hypo  fixing  bath.  This 
neutralizing  action  of  the  short-stop  bath  is  important  because  it  imparts 
longer  life  to  the  acid  hypo  fixing  bath  and  a  more  uniform  action  of 
same.  If  this  acid  rinse  bath  is  used,  the  fixing  bath  will  fix  out  almost 
twice  as  many  prints  as  it  would  if  no  short-stop  bath  were  used. 
One  quart  (one  liter)  of  the  short-stop  bath  will  process  about  twenty 
8  x  10  prints  or  their  equivalent  of  smaller  prints.  Properly  prepared,  an 
acid  fixing  bath  (one  quart)  will  fix  out  approximately  thirty  8  x  10  prints 
or  their  equivalent  in  other  sizes  if  the  short-stop  bath  is  used  between 
development  and  fixation  or  about  one-half  that  number  of  prints  if  only 
an  ordinary  water  rinse  is  used. 

A  short-stop  bath  is  prepared  by  diluting  one  and  a  half  ounces  of 
acetic  acid  (28%)  with  32  ounces  of  water  (or  48cc  to  one  liter  of  water). 
If  28%  of  acetic  acid  is  not  available  same  may  be  prepared  from  glacial 
acetic  acid  (a  much  more  economical  way)  by  diluting  three  parts  of  glacial 
acetic  acid  with  eight  parts  of  water.  It  should  be  remembered  that  only 
a  short  rinse  in  this  short-stop  bath  is  required  (from  five  to  ten  seconds) 
while  longer  immersion  (one  minute  or  more)  will  degrade  the  tones  of 
most  enlarging  paper,  will  cause  blisters  and  general  disintegration  of  the 
emulsion  of  the  print. 


Fixation  is  of  utmost  importance,  as  upon  its  thoroughness  depends  in 
a  large  measure  the  permanence  of  the  photographic  print.  Preparation  of 
an  acid  fixing  bath  should  be  done  as  carefully  as  that  of  development. 
Fixation  is  generally  complete  within  ten  to  fifteen  minutes,  provided  every 
surface  of  the  print  has  full  access  to  the  bath  and  that  the  prints  do  not 
stick  together.  The  prints  are  best  kept  moving  in  the  fixing  bath. 

There  are  three  ways  of  preparing  an  acid  fixing  bath:  First,  for  the 
workers  who  do  not  turn  out  great  quantities  of  prints  a  very  satisfactory 
way  of  preparing  hypo  is  by  purchasing  ready  put  up  packages  of  powders, 
which  contain  all  necessary  ingredients,  and  follow  instructions  on  each  box. 

Second,  for  those  who  do  more  work  and  like  to  prepare  their  own, 
the  following  formula  is  most  satisfactory  and  generally  used: 

Water  64  ounces  2  liters 

Hypo  16        "  480  grams 


When  thoroughly  dissolved,  add  the  entire  quantity  of  the  following: 

Hardening-  Solution  Separately  Prepared 
Water  (at  about  125°  F.)       5  ounces        160  cc 
Sodium  Sulphite  (dry)  1  ounce  30  grains 

Acetic  Acid  (28%)  3  ounces  96  cc 

Potassium  Alum  1  ounce  30  grams 

Dissolve  the  sulphite  completely  before  adding  the  acetic  acid.  After 
the  sulphite-acid  solution  has  been  mixed  thoroughly,  add  the  potassium 
alum  with  constant  stirring.  When  the  alum  is  dissolved  entirely,  harden- 
ing solution  should  be  cooled  after  mixing  and  slowly  added  to  the  cool 
hypo  solution  while  stirring  the  latter  rapidly. 

The  third  method,  for  those  who  require  large  quantities  of  hypo  to  be 
kept  for  considerable  time,  is  to  prepare  an  acid  fixing  bath  by  dissolving 
two  pounds  of  hypo  in  a  gallon  of  water  and  keeping  it  in  a  well  stoppered 
bottle.    Separately  a  stock  hardener  solution  is  prepared  as  follows: 
Water  (at  about  125°  F.)        56  ounces          1700  cc 
Sodium  Sulphite  (dry)  8        "  240  grams 

Acetic  Acid  (28%)  24       "  750  cc 

Potassium  Alum  8       "  240  grams 

Cold  water  to  make  1  gallon  4  liters 

Dissolve  the  chemicals  in  the  order  given,  following  instructions 
given  for  formula  above. 

The  fixing  bath  is  quickly  made  by  adding  one  part  of  this  stock  hard- 
ener to  four  parts  of  cool  hypo  solution. 

Finally,  a  very  effective  and  economical  method  of  securing  hypo  for 
prints  is  to  provide  a  large  bottle  and  to  pour  into  it  all  the  hypo  that  has 
been  used  once  and  not  more  than  twice  for  fixing  of  negatives.  Such 
hypo  is  good  enough  for  prints  and  makes  it  more  practical  to  use  fresh 
hypo  for  every  film  treated. 

It  would  seem  unnecessary  to  warn  against  the  use  of  old  worn  out 
baths,  but  somehow  everybody  seems  to  do  it.  Hypo,  Acetic  Acid,  Alum 
and  Sodium  Sulphite  are  cheap  (even  the  water  hasn't  been  so  highly  taxed 
as  some  things  as  yet).  Your  time  and  effort  in  getting  a  print  as  you  want 
it  are  valued  at  your  own  price;  a  worn  out  bath  can  stain  every  print  and 
you  won't  know  it  until  you  turn  the  bright  lights  on.  Don't  take  the 
chance!  Another  suggestion,  thirty  seconds  devoted  to  moving  each  print 
about  in  the  hypo  when  first  brought  over  will  insure  even  fixing  and  prevent 
unaccountable  rings,  and  other  marks  from  appearing  during  any  later 
treatment.  One  more,  when  a  bath  becomes  milky,  either  through  use  or 
old  age,  throw  it  away. 


Having  brought  a  print  to  this  point  with  success,  one  looks  for- 
ward to  the  prideful  joy  he  will  experience  when  showing  it  to  friends 
and  then  tosses  it  into  a  tray  of  water  into  which  a  dozen  other  prints 
will  be  similarly  tossed  before  the  first  is  removed,  supposedly  com- 
pletely washed.  "With  the  water  running  full  force  a  print  cannoi 
be  thoroughly  free  of  hypo  if  other  prints  have  been  continually 
brought  over  from  the  hypo  bath.  Washing  should  continue  for 
at  least  a  full  hour  after  the  last  print  has  been  brought  over, 
preferably  rinsing  each  print  as  it  is  taken  from  the  hypo,  "Washing; 


Enlarging  Papers 

cannot  be  stressed  enough  if  permanency  is  desired,  as  any  trace  of 
cliemical  left  in  the  paper  will  discolor  or  fade  the  print,  perhaps 
not  in  the  first  six  months,  but  a  well  washed  print  will  last  for  years. 
Thoroughness  of  washing  after  fixing  is  just  as  important  as 
every  other  step  in  preparing  a  good  print.  A  print  insufficiently 
washed  will  deteriorate  just  as  a  print  insufficiently  fixed.  Tin* 
water  used  for  washing  prints  should  not  be  colder  than  65°  nor 
warmer  than  75  to  80°.  "Washing  should  be  complete  in  an  hour's 
time  if  the  prints  are  moved  about  and  the  water  constantly  changed. 
The  Eastman  Kodak  Company  makes  and  sells  an  excellent  tray 
syphon  which  if  used  in  accordance  with  instructions  accompanying 
it,  makes  a  most  ideal  aid  for  thorough  washing  of  prints.  This  device 
is  easily  attached  and  is  absolutely  fool-proof  and  safe  in  its  operation. 

Hypo  Test 

It  is  highly  advisable  to  apply  a  very  simple  hypo  test  to  be  sure  that  the 
prints  are  completed  washed. 

The  following  Hypo  Test  Solution  is  recommended  by  the  East- 
man Kodak  Company  and  is  known  as  Formula  HT-la: 

Avoirdupois  Metric 

Potassium   Permanganate    4  grains  0.3  gram 

Sodium  Hydroxide  (Caustic  Soda) ...     8  grains  0.6  gram 

Water   (distilled)   to  make 8  ounces  250.0  cc. 

To  make  the  test,  take  4  ounces  (125cc.)  of  distilled  water  in  a 
clear  glass  and  add  %  dram  (Ice.)  of  the  permanganate-caustic 
soda  solution.  Pour  %  ounce  (15cc.)  of  this  diluted  solution  into 
a  clean  1-ounce  graduate.  Then  take  six  4"  x  5"  prints  or  their 
equivalent  from  the  wash  water  and  allow  the  water  from  them 
to  drip  for  30  seconds  into  the  %  ounce  of  test  solution.  If  a 
small  percentage  of  hypo  is  present  the  violet  color  will  turn 
orange  in  about  30  seconds  and  become  colorless  in  about  one 
minute.  In  such  case  the  prints  should  be  further  washed  until 
no  color  change  is  produced  by  the  test  which  proves  that  the 
hypo  has  been  eliminated. 


Drying  the  print  offers  very  little  difficulty  if  a  few  points  are 
remembered.  Curling  is  due  to  uneven  drying  more  than  anything 
else.  If  the  surface  water  is  not  wiped  oif ,  it  will  collect  in  pools 
leaving,  at  times,  dents  in  the  print  which,  when  finally  dried  out, 
shows  strain  marks  in  the  gelatin.  A  print  carefully  wiped  dry  with 
a  viscose  sponge  and  then  dried  on  cheese  cloth,  face  down,  will 
have  so  little  curl  as  to  flatten  of  its  own  accord  when  filed  away. 
Even  when  dried  face  up  on  a  blotter,  the  curl  is  not  objectionable. 
The  Eastman  Kodak  Company  produce  a  print  drying  roll  con- 


sisting  of  a  long  length  of  corrugated  paper  together  with  two  similar 
lengths  of  blotting  paper,  the  one  faced  with  a  specially  prepared 
cloth  to  prevent  sticking  to  the  face  of  the  print.  The  two  lengths 
of  blotting  paper  and  the  corrugated  paper  are  rolled  over  a  card- 
board tube,  forming  a  roll  approximately  10"  in  diameter.  Prints  to 
be  dried  are  laid  between  the  blotters  facing  the  cloth.  The  roll 
may  be  placed  before  a  fan  or  left  standing.  When  the  prints  are 
dry  they  will  be  found  to  have  a  backward  curl,  quickly  becoming 
flat  when  removed. 


There  are  two  types  of  tins  available  for  f  errotyping  prints  requiring 
high  gloss  finish.  The  least  expensive  are  black  enamel  tins.  Slightly 
more  expensive  but  very  practical  are  chromium  plated  tins.  Either  type 
will  produce  excellent  results  indefinitely  if  they  are  well  cared  for.  They 
scratch  easily  and  should  be  protected  from  rough  handling,  grit  and  dirt 
They  should  be  carefully  washed  with  a  wet  chamois  or  viscose  sponge 
directly  after  use.  When  stored  they  should  be  interlined  with  line  paper  or 
wax  paper,  placed  face  to  face.  Do  not  allow  your  chemicals  or  solutions 
to  remain  on  your  ferrotyping  tins  for  any  length  of  time  as  they  will  eat 
into  the  enamel  eventually  causing  blisters  and  corrosion,  thus  rendering  the 
tins  useless. 

Ferrotyping  to  produce  really  glossy  prints  is  not  a  difficult  matter  if 
a  few  precautions  are  followed.  Glass,  coated  with  paraffin  or  beeswax  has 
been  suggested  from  time  to  time  but  is  never  really  successful.  Ferrotype 
tins  are  too  cheap  to  consider  such  substitutes.  The  tin  must  be  thoroughly 
cleaned  with  a  soft  cloth  and  a  few  drops  of  benzene  or  hot  water  every 
time  any  particle  is  noticed  to  be  adhering  from  the  last  prints.  The  tin 
should  then  be  lubricated  with  a  solution  of  paraffin  in  benzene  (10  grains 
of  paraffin  to  1  oz.  of  benzene,  1  gram  to  50cc).  A  few  drops  of  this  solu- 
tion rubbed  evenly  over  the  tin  and  then  polished  gently  with  a  soft  cloth 
is  sufficient;  this  need  not  be  repeated  unless  it  becomes  necessary  to  clean 
the  tin  with  hot  water  or  benzene  to  remove  particles  stuck  to  the  tin. 
Normally  it  suffices  to  polish  the  tin  with  a  soft  cloth  each  time  it  is  used. 
Only  glossy  paper,  specially  coated  for  ferrotyping  during  manufacture, 
should  be  used.  The  print  should  be  brought  from  the  wash  water,  rinsed 
under  the  tap,  and  without  draining  laid  face  down  on  the  tin  and  squeezed 
dry.  Too  much  pressure  may  cause  the  prints  to  stick;  not  enough,  and  they 
will  not  get  good  contact  with  the  tin  and  will  have  an  uneven  gloss.  Little 
difficulty,  however,  will  be  experienced  as  the  latitude  is  considerable.  The 
tins  are  then  set  aside  to  dry  in  any  warm  spot  with  a  current  of  air,  such 
as  a  window.  Drying  should  take  several  hours  at  least;  artificial  heating 
is  not  good,  causing  sticking  and  uneven  drying  which  leaves  strain  marks. 
If,  on  the  other  hand  the  prints  are  left  in  a  damp  place,  or  sufficient  air 
is  not  allowed  around  them,  such  as  setting  one  tin  next  to  another 
separated  by  only  a  fraction  of  an  inch,  the  drying  will  proceed  from  the 
edges  in  and  a  ring  shaped  strain  mark  will  develop.  When  dry,  the  prints 
fall  off  of  their  own  accord  or  will  peel  off  readily  if  a  corner  is  loosened 
with  a  knife.  Brown  stains  sometimes  appear  on  the  surface  of  ferrotvped 


Enlarging  Papers 

prints,  due  to  insufficient  rinsing  of  the  print  or  the  tin.  A  damp  cloth  will 
wipe  this  dirt  away  without  affecting  the  gloss.  Insufficient  washing  will 
leave  hypo  in  the  print  which  turns  yellow  and  cannot  be  remedied.  Grains 
of  dirt  or  bits  of  gelatine  stuck  to  the  tin  produce  little  holes  in  the  print 
which  cannot  be  remedied.  Ferrotyping  on  glass  produces  a  waxy  looking 
surface  which  is  anything  but  desirable.  Cleaning  with  benzene,  soaking 
and  referrotyping  on  a  tin  will  produce  excellent  results. 


There  are  two  relatively  simple  methods  of  sepia  toning  depending 
for  their  action  on  the  conversion  of  the  silver  image  to  silver  sulphide. 
By  bleaching  the  regular  bromide  print  in  a  solution  of  Potassium  Ferri- 
cyanide  and  then  redeveloping  the  bleached  image  in  Sodium  Sulphide 
very  excellent  sepia  tones  may  be  obtained.  The  bleaching  solution  will 
keep  indefinitely  and  is  as  follows: 

Water  (cold)  32  ounces  I  liter 

Pot.  Ferricyanide  200  grains  14  grams 

Pot.  Bromide  200  grains  14  grams 

Liquid  Ammonia  20  drops  20  drops 

When  prints  have  been  fixed,  wash  thoroughly  to  remove  any  trace  of 
hypo;  prints  on  rough  surface  papers  should  be  thoroughly  dried  before 
bleaching,  others  may  be  bleached  without  intermediate  drying.  Bleach 
until  the  image  is  but  faintly  visible.  Wash  all  the  yellow  stain  away  under 
the  tap  and  redevelop  in  the  following: 

Water  32  ounces  1  liter 

Sodium   Sulphide  200  grains  14  grams 

Redevelopment  takes  but  a  minute,  after  which  the  print  should  be  thor- 
oughly washed  and  dried.  To  obtain  Brown-Black  tones  do  not  bleach  com- 
pletely. Dilute  the  bleaching  bath  5  to  1  to  facilitate  even  bleaching  and 
rinse  off  when  the  image  is  about  half  bleached. 

The  second  method  depends  on  the  action  of  alum  on  hypo  to  form  the 
sulphide.  The  bath  is  made  up  as  follows: 

Water  32  ounces  1  liter 

Hypo  4  ounces  100  grams 

Alum  1  ounce  30  grams 

The  above  solution  is  milky  in  appearance  and  should  not  be  filtered,  but 
before  use  it  must  be  ripened  to  avoid  bleaching  the  prints.  Toning  is  done 
between  90°  and  115°  F.  taking  from  30  to  60  minutes. 

The  bath  may  be  ripened  by  toning  three  or  four  old  discarded  prints 
or  by  the  addition  of  the  following: 

Silver  Nitrate  8       grains  0.5  grams 

Common  Salt  8       grains  0.5  grams 

Water  2l/4  ounces  70  cc 

Toning  may  also  be  carried  out  in  the  cold  solution,  taking  from  6  to 
24  hours.  An  excellent  plan  is  to  keep  a  bath  in  the  dark  room  at  all  times 
and  tone  all  discarded  prints  as  well  as  those  which  it  is  purposely  planned 
to  tone.  By  using  the  cold  solution  the  process  is  fool  proof,  toning  being 
even  throughout  the  print  if  it  is  first  moved  about  to  insure  even  wetting. 
The  prints  may  be  left  in  the  bath  almost  indefinitely  without  harm.  By 
toning  discarded  prints,  many  unusual  things  will  be  discovered. 

Those  prints  which  it  is  planned  to  tone  should  be  printed  slightly 
darker  than  is  desired  as  the  toned  print  is  several  shades  lighter  than  the 


black  and  white  original.     If  the  hypo  alum  bath  is  not  ripened  the  first 
few  prints  will  lose  their  delicate  details. 

There  are  numerous  other  methods  of  toning  to  obtain  different  colors, 
but  their  use  is  not  recommended  to  the  beginner.  Many  manufacturers 
issue  pamphlets,  obtainable  through  their  dealers,  describing  these  processes. 


Miniature  camera  work  requires  great  care  and  cleanliness  in 
every  step  of  the  process,  including  the  storing  of  the  negatives  and 
their  handling  during  inspection  or  use.  However,  no  matter  how 
much  care  is  exercised,  prints  will  show  occasional  dust  spots  and 
more  rarely,  dark  spots,  due  to  pin  holes  or  minute  scratchings  in 
the  film.  The  removal  of  the  latter  is  difficult,  being  impossible  on 
glossy  prints  and  requiring  very  delicate  use  of  the  retouching 
knife  on  matt  and  semi-matt  prints.  Spotting  the  former  is  not  so 
difficult  with  a  little  experience. 

The  hardest  part  of  spotting  prints  is  to  find  a  pencil,  crayon 
or  paint  which  will  match,  the  print  not  only  in  color  but  also  in 
gloss.  Pencils  are  effective  only  on  a  matt  or  rough,  surface  where 
the  slight  gloss  of  a  pencil  closely  matches  that  of  the  paper.  For 
most  papers  with  matt  surfaces,  the  carbon  type  pencils,  which  have 
almost  no  gloss  at  all,  are  very  satisfactory.  On  the  semi-matt  papers 
ordinary  soft  retouching  pencils  are  often  quite  satisfactory.  For 
sepia  toned  prints  on  semi-matt  surfaces,  sepia  crayons  can  be  used. 
Fine  spotting  brushes  with  Chinese  India  Ink  are  very  satisfactory 
if  the  tones  of  the  print  are  real  black,  such,  as  obtained  from  con- 
tact paper  when  very  little  bromide  has  been  used  in  the  developer. 

For  really  good  results  on  all  kinds  of  papers,  a  medium  such  as 
paint  which  is  flexible  both  as  to  color  and  gloss  is  necessary.  The, 
one  drawback  to  paint,  however,  is  the  fact  that  for  single  prints 
or  even  to  spot  less  than  say  half  a  dozen  prints  at  one  time,  it  is 
necessary  to  go  to  considerable  bother  in  preparation.  Some  spotting 
colors  are  available  on  glazed  paper  cards  but  the  most  satisfactory 
method  is  to  obtain  artist's  water  colors,  coming  in  tiny  trays.  Three 
colors  are  really  necessary,  lamp  black — dull,  blue  black — dull,  and 
burnt  sienna — slightly  glossy.  For  mixture  with  the  above  to  obtain 
the  necessary  gloss  a  tube  of  Talen's  blackish  and  another  of  Talen's 
brownish  should  be  obtained.  The  total  cost  of  the  above,  together 
with  a  good  spotting  brush,  would  be  about  two  dollars  and  would 
last  for  many  years. 

Using  a  small  bit  of  opal  glass  for  a  palette,  carry  a  bit  of  the 
dull  color  on  your  wet  finger  to  the  glass.  To  this  should  be  added 



Albert  Simmons 

some  of  the  glossy  color,  until,  as  mixed  with  the  finger  on  the  glass, 
the  color  appears  to  be  slightly  more  glossy  than  the  print.  Some 
experimenting  will  be  necessary  before  the  right  sheen  can  be  recog- 
nized, but  it  should  always  be  remembered  that  the  dull  paints  have 
less  sheen  than  has  the  roughest  matt  paper,  with  the  possible  excep- 
tion of  such  special  finishes  as  Gevalux.  Moisten  the  brush  with  a 
turning  motion  in  a  drop  of  water  on  the  palette,  wiping  off  any 
excess  water  with  the  same  turning  motion  on  a  bit  of  photographic 
blotter,  still  turning  the  brush  in  the  same  direction,  take  up  a  bit 
of  the  mixed  color  and  apply  to  the  print  in  very  small  dots.  Do 
not  attempt  to  finish  the  job  in  one  operation,  keep  the  dots  separated, 
letting  them  dry  while  working  on  a  different  portion  of  the  print 
and  then  coming  back,  several  times  if  necessary,  to  fill  in  the  spaces 
between  the  dots.  If  the  brush  is  not  too  wet  and  if  the  minimum 
amount  of  water  has  been  used  in  mixing  the  colors,  it  will  be  found 
that  by  very  light  strokes  nice  even  dots  can  be  made  which  will 
not  smear  or  vary  appreciably  in  color  when  dry.  The  smallest  pin 
holes  appearing  in  a  print  usually  require  about  three  of  these  fine 
dots  to  be  properly  concealed.  If  it  is  attempted  to  put  one  large  dot 
in  these  holes,  the  paint  will  dry  in  a  little  lump  which  will  usually 
rub  off  after  it  has  dried.  In  using  an  etching  knife  to  remove  dark 
spots,  such  as  are  caused  by  pin  holes  in  the  negative,  it  will  usually 
be  found  most  successful  to  carry  the  operation  a  shade  beyond  the 
adjoining  tones,  spotting  with  the  proper  color  so  as  to  obtain  the 
right  gloss,  since  on  glossy  prints  any  knife  work  leaves  a  matt 
surface  and  on  matt  prints  knife  work  leaves  a  semi-gloss  surface. 

Another  method  of  spotting  matt  prints,  particularly  suitable 
for  portrait  work,  or  where  large  areas  are  to  be  covered,  such  as 
working  in  backgrounds  or  clouds,  is  the  use  of  chalks.  These  can 
be  obtained  in  blocks  from  artists '  supply  stores  or  can  be  prepared  at 
home  from  the  filing  obtained  when  sandpapering  retouching  pencils 
to  a  fine  point.  The  only  things  which  must  then  be  bought  are 
stumps  and  pumice  powder  (used  by  draughtsmen  on  tracing  cloth 
for  making  the  ink  hold  and  obtainable  from  most  artists'  supply 
stores).  Excellent  stumps  can  be  made  at  home  after  a  little  practice 
by  rolling  lengths  of  paper  on  a  diagonal  so  as  to  obtain  different 
sized  points.  However,  soft  chamois  and  paper  stumps  cost  little. 

The  print  is  first  rubbed  lightly  with  pumice  to  eliminate  any 
possible  grease  and  the  chalk,  mixed  with  a  little  pumice,  is  then 
rubbed  on  and  worked  with  a  stump  to  the  necessary  shade.  For 


Enlarging  Papers 

large  areas,  such  as  working  in  backgrounds  or  clouds,  a  ball  of 
cotton  dipped  into  the  mixture  of  pumice  and  chalk  is  used  to  cover 
the  area,  the  larger  stumps  then  being  used  to  work  in  the  shading 
and  detail.  In  working  in  backgrounds  a  soft  eraser  can  be  used  to 
break  the  outline  in  long  slanting  strokes,  a  soft  bit  of  clean  cotton 
then  being  used  to  soften  the  edges  of  the  breaks  and  smooth  out  the 
outlines.  Some  experimenting  and  a  considerable  study  of  studio 
portraits  will  be  necessary  before  really  good  work  of  this  sort  can 
be  done.  To  fix  the  chalk  to  avoid  rubbing,  etc.,  provide  a  large  tray 
of  water.  The  tray  should  be  considerably  larger  than  the  print  and 
should  contain  about  2  inches  of  water,  more  if  possible.  Holding 
the  print  by  both  ends,  give  it  a  considerable  curve  and  in  one  move- 
ment draw  it  into  the  water,  to  the  bottom  of  the  tray  and  out  at 
the  other  end  of  the  tray.  Allow  the  water  to  drain  off  one  end  and 
without  shifting  the  position  of  the  print  hang  it  up  to  dry.  Streaks 
will  appear  if  the  movement  of  the  print  through  the  water  is  jerky 
or  if  the  print  is  moved  around  while  the  water  is  draining  off. 

When  Matte  and  Semi  Matte  Papers  are  used  a  light  coating  of 
wax  often  lends  a  beautiful  luster  to  the  print.  "Waxing  prepara- 
tions may  be  obtained  from  your  dealer.  In  applying  them  it  is  best 
to  use  a  small  pad  of  cheesecloth  to  apply  a  little  wax  over  the  entire 
print,  then  quickly  rubbing  off  the  excess  with  a  clean  cloth.  Some 
preparations  require  considerable  time  to  dry;  others  can  be  handled 
within  an  hour.  The  bottle  should  give  all  necessary  information. 

Presentation  of  the  Finished  Prints 

One  phase  of  photography  which  is  almost  totally  ignored  by 
the  average  worker,  is  the  presentation  of  his  print.  Not  that  the 
frame  is  required  to  appreciate  the  beauty  of  a  picture,  but  it  does 
help  considerably.  The  average  album  of  snapshots  is  undoubtedly 
the  best  illustration  of  the  worst  method  of  presenting  prints.  If  the 
prints  are  to  be  mounted  in  albums,  considerable  thought  should  be 
given  to  the  size  of  the  prints,  the  widths  of  their  borders,  and  the 
color  of  the  stock  in  comparison  with  the  size  and  color  of  the  album. 
Prints  in  black  and  white  do  not  show  up  effectively  on  buff  or  ivory 
stock  nor  are  they  as  effective  in  an  album  the  pages  of  which  are  of 
buff  or  have  a  brown  tone.  They  should  be  mounted,  preferably, 
on  white  or  gray.  Similarly,  buff  prints  or  sepias  look  their  best 
against  the  background  having  brown  or  buff  tones.  The  mounting 
of  the  prints  in,  the  album  should  be  tasteful  rather  than  convenient. 
The  use  of  tissue,  black,  brown  or  white,  under  the  print  and  showing 


a  narrow  edge,  is  very  effective.  After  some  experience,  the  amateur 
with  a  taste  for  modern  contrasts  will  learn  to  use  tissues  of  such 
striking  colors  as  red  or  blue. 

For  prints  to  be  shown  separately,  mountings  on  heavy  stock 
are  to  be  recommended.  The  simplicity  and  taste  which  is  shown  in 
the  choice  of  the  stock  and  the  method  of  mounting  will  be  the  key- 
note of  its  success,  yet  it  is  a  relatively  simple  matter  to  prepare 
such  mountings. 

Embossing  Prints 

The  simplest  of  all  is  the  embossed  print.  For  this,  it  is  neces- 
sary to  carefully  plan  the  print  so  that  no  trimming  of  the  picture 
is  necessary.  Sufficient  border  is  left  to  properly  frame  the  finished 
picture,  somewhat  more  at  the  bottom  than  at  the  top  and  sides.  A 
piece  of  card  is  then  chosen,  about  the  same  thickness  as  the  stock 
or  slightly  thicker;  this  is  trimmed  the  same  shape  as  the  picture 
but  a  trifle  larger.  If  a  heavy  glass  plate  is  available  a  light  is 
placed  under  it,  the  card  just  trimmed  laid  on  that  and  the  picture 
placed  face  down  over  the  card  and  adjusted  to  leave  an  equal  border 
around  the  pieturd.  With  an  embossing  tool,  the  back  of  a  tooth 
brush  or  knife  handle,  the  stock  is  rubbed  equally  all  around  the 
edge  of  the  card,  causing  the  picture  area,  when  viewed  from,  the 
face,  to  be  sunk  behind  the  border.  Many  variations  will  suggest 
themselves  to  the  imagination,  such  as  beadings,  double  borders,  etc. 
The  print  thus  embossed  may  then  be  trimmed  to  equalize  the  borders. 
The  edges  may  be  roughened  by  laying  the  print  on  the  table  with 
the  edge  out  to  the  table  edge  and  scraping  with  a  sharp  knife. 

In  cutting  the  card  so  as  to  make  window  mounts,  cut  from  the 
back  and  against  a  hard  surface  so  as  to  leave  a  smooth  edge.  To 
cut  on  an  angle,  lay  a  steel  or  other  thin  ruler  under  the  knife,  hold- 
ing the  knife  firmly  and  keeping  the  blade  of  the  knife  and  the  nail 
of  the  index  finger  firmly  against  the  guide — thus  maintaining  a  con- 
stant angle. 

The  final  step  in  mounting,  particularly  for  Christmas  cards,  is 
the  book  or  folder.  The  print  may  simply  be  placed  in  the  folder, 
or  a  card  mount  nicely  embossed,  or  again  a  window  mount  may  be 
prepared  and  the  whole  placed  in  the  folder.  The  folder  preferably 
should  be  of  lighter  material  than  the  card  used  as  a  mount  in  the 
last  two  cases,  although  like  everything  else,  this  is  really  a  matter 
of  taste  and  individuality.  A  tissue  paper  fly  leaf  may  or  may  not 
be  inserted.  The  cover  may  have  some  design  embossed  into  it  or 


Enlarging  Papers 

may  be  printed  with  a  linoleum  or  wood  block.  Any  number  of 
variations  suggest  themselves  and  much  pleasure  will  be  derived  from 
making  individual  mounts. 

One  word  about  pasting.  Library  paste,  homemade  paste  and 
any  glue  will  do  the  job.  Some  contain  products  which  will  injure  a 
photograph,  but  most  are  quite  satisfactory.  However,  for  a  neat 
and  convenient,  as  well  as  reliable  job,  nothing  is  as  satisfactory  as 
dry  mounting  tissue.  A  hand  iron,  kept  nicely  warm,  or  if  of  the 
automatic  type,  set  at  a  low  heat,  is  just  right  for  mounting  pictures 
up  to  11"  by  14"  and  the  thinnest  mounts  will  lie  flat. 

Eubber  cement  is  probably  the  best  and  the  cleanest  mountant. 
It  should  be  spread  with  a  large  brush  over  both  the  mount  and  the 
print  and  allowed  to  dry  for  more  than  a  half  hour.  The  print 
must  then  be  carefully  adjusted  to  guide  marks  previously  made  on 
the  mount,  for  once  placed  it  will  be  impossible  to  move  the  print. 
Any  excess  cement  around  the  edges  can  be  removed  with  a  soft 
cloth.  Do  not  get  rubber  cement  on  waxed  prints  as  it  removes 
the  wax.  When  using  paste  glue  or  cement  the  mounted  print 
should  be  placed  under  light  pressure  for  a  short  while  before  putting 
in  a  press  or  under  heavy  pressure  for  final  drying.  When  transfer- 
ring from  the  light  to  the  heavy  pressure  a  careful  inspection  should 
be  made  to  be  sure  no  paste  or  cement  has  oozed  out  at  the  edges  of 
the  print. 

Many  advanced  workers  are  using  thin  papers  for  paper  nega- 
tives,- a  beautiful  result  can  be  obtained  by  printing  on  the  thinnest 
papers  available  and  carefully  mounting  on  medium  weight  mounts. 
This  is  particularly  satisfactory  for  Christmas  cards.  Thin  papers 
must  be  treated  carefully  to  avoid  air  bells  in  the  developer  and  hypo. 

And  so  a  little  has  been  said  regarding  many  things.  Perhaps  a 
first  reading  has  confused  some  or  led  others  to  believe  that  the 
whole  matter  is  unnecessarily  involved.  I  hope,  however,  that  in 
some  way  many  who  have  read  this  chapter  will  become  more  keenly 
appreciative  of  the  importance  of  printing  as  one  of  the  major  steps 
in  producing  a  photograph;  far  too  little  has  been  said  to  date 
regarding  this  angle  of  photography,  each  newcomer  apparently  be- 
ing expected  to  struggle  along  until  somehow  he  succeeds  in  turning 
out  one  or  two  good  prints  from  each  package  of  paper  he  buys. 
If,  as  has  been  stressed  several  times  before,  the  beginner  will  stick 
to  one  paper,  one  developer,  etc.,  until  lie  is  turning  out  a  fair  aver- 
age of  good  prints,  he  should  find  that  lie  has  learned  to  do  this 
with  very  little  waste  of  paper  and  time. 


Fig.  118  A  Dandelion  Gone 
to  Seed. .  .Photo  by  Wm.  M. 

135mm  Elmar  lens,  f:36,  5  sec- 
onds, Panatomic.  Sliding  Copy 
Attachment  used. 

Fig.  119      Sprouting  Peas 


J.  M.  Leonard 



Data  Tables  by  Henry  M.  Lester 

In  ordinary  use  the  Leiea  cannot  be  adjusted  for  photographing 
objects  at  distances  less  than  3y2  feet  without  the  aid  of  special  sup- 
plementary front  lenses  or  one  of  the  copy  attachments.  Thus  the 
3^  foot  mark  becomes  the  dividing  line  or  norm  for  the  Leica  user 
who  is  interested  in  photographing  large  or  small  objects.  Let  us 
step  across  the  threshold  of  this  3%  foot  mark  and  explore  the 
wonders  of  the  world  of  small  objects.  What  a  contrast!  In  the 
large  object  field  we  were  photographing  people,  buildings,  moun- 
tains, and  even  the  moon  or  sun  far  out  into  the  space  of  infinity. 
Yet  in  the  small  object  world  there  is  a  universe  in  itself  to  be 
explored  by  the  inquisitive  mind.  Here  a  book  page  may  be  copied 
or  a  micro-organism  photographed  on  the  Leica  negative  with  a 
2,000  times  magnification.  A  truly  amazing  contrast  from  infinity 
to  2,000  times  magnification.  The  user  of  a  Leica  can  readily  span 
this  gap. 

Intensive  work  in  photographing  the  large  object  world  has  been 
carried  on  for  nearly  a  century.  However  it  has  only  been  in  recent 
years  that  small  object  or  micro  photography  has  become  an  essen- 
tial part  of  our  daily  living,  mainly  because  of  the  important  ad- 
vances in  camera  design.  The  eye  of  the  camera  was  made  to  peer 
into  the  inner  structure  of  the  world.  All  the  large  hospitals  and 
educational  institutions  have  elaborate  photographic  departments 
equipped  for  the  close-up  micro  photography  of  specimens  which 
are  invaluable  for  future  reference  by  the  medical  and  teaching  staff. 
Police  departments  use  the  camera  for  close  up  photography  just 
as  nimbly  as  they  use  their  guns.  Industrial  firms  keep  constant 
photographic  records  of  their  products  which  may  be  used  for  refer- 
ence, sales,  or  advertising  purposes.  The  visual  education  field  is 
an  important  user  of  close  up  or  small  object  photography  for  pre- 
senting thousands  of  different  subjects  on  the  projection  screen  or 
by  actual  photographs  to  millions  of  students.  Such  examples  show 


us  how  Immense  and  likewise  important  the  field  of  small  object 
photography  has  become.  Let  us  now  learn  how  to  use  our  Leica 
camera  for  this  type  of  work. 

Practically  everyone  who  uses  a  camera  has  had  the  occasion  to 
make  close-up  photographs  of  objects.  Such  pictures  may  have  been 
more  or  less  successful  depending  upon  the  camera  and  experience 
of  the  operator.  The  copying  possibilities  of  a  camera  should  really 
be  looked  upon  as  the  visual  note  book  which  is  indispensable  for 
keeping  accurate  records  of  any  object,  such  as  machine  parts,  draw- 
ings, manuscripts,  geological  specimens,  medical  subjects,  or  small 
magnified  pictures  of  insects.  In  fact  it  may  be  said  that  anything 
can  be  copied  that  can  be  illuminated  adequately  for  photographic 

If  you  are  a  student  the  copy  camera  outfit  can  quickly  be 
applied  for  illustrating  your  biology  note  book,  or  possibly  you  may 
need  references  from  rare  books  which  can  not  be  removed  from  the 
library.  In  the  latter  case  the  camera  can  be  utilized  perfectly  and 
at  a  minimum  expense.  The  developed  negatives  may  be  placed  in  a 
projector  or  enlarger  and  read  directly  from  the  projected  image. 

Importance  of  Small  Object  Photography 

This  chapter  on  Small  Object  Photography  should  be  studied 
carefully  because  it  is  the  basis  upon  which  other  chapters  have  been 
prepared.  A  thorough  knowledge  of  the  copying  equipment  and 
methods  will  enable  you  to  grasp  a  complete  understanding  of  the 
following  chapters  which  are  so  closely  related  to  the  present  chapter : 

A.  The  Leica  as  an  Ophthalmic  Camera. 

B.  Miniature  Camera  for  Miniature  Monsters. 

C.  Making  Leica  Film  and  Glass  Slides. 

D.  Dental  Photography  with  the  Leica. 

E.  Photomicrography  with  the  Leica. 

F.  The  Leica  in  Visual  Education. 

G.  Historical  Keseareh  with  a  Leica. 

Close  up  photography  of  small  objects  really  has  a  field  and  technique 
quite  different  from  the  usual  type  of  photographic  work  which  is  prac- 
ticed by  everybody  who  can  focus  a  camera  and  click  the  shutter.  When 
we  start  taking  photographs  of  a  butterfly,  newspaper  clipping,  flower, 
mineral  specimen,  or  any  small  object,  a  number  of  special  problems  arise. 

1.  The  camera  requires  additional  equipment. 

2.  Focusing  becomes  more  critical  as  depth  of  focus  decreases. 

3.  Exposure  factors  change  and  are  calculated  according  to  the  degree  of 
magnification  required. 

4.  Proper  illumination  becomes  an  extremely  important  problem. 



5.  It  is  often  necessary  to  use  color  filters  in  order  to  obtain  certain  re- 

6.  The  Leica  camera  and  auxiliary  equipment  must  be  mounted  on  a  rigid 
base,  free  from  vibration. 

7.  The  proper  film  must  be  selected  for  use  with  the  various  types  of  copy 

8.  Even  the  specimens  to  be  copied  should  be  mounted  or  properly  ar- 
ranged in  order  to  insure  a  perfect  reproduction  on  the  negative.     As 
the  final  picture  will  be  reproduced  in  black  and  white,  or  monotone, 
it  is  important  to  select  objects  which  will  produce  the  best  contrasts 
and  details  required. 

As  most  of  us  are  not  equipped  with  spacious  photographic  studios 
our  camera  equipment  should  be  small,  light,  and  easily  portable. 

Even  the  developing  technique  is  of  great  importance  for  films  made 
of  small  objects. 

Once  the  proper  equipment  has  been  assembled  for  any  type  of  close 
up  photography  there  will  be  many  interesting  objects  to  photograph.  In 
fact  you  will  begin  to  see  a  new  world  in  miniature. 

Accessories  for  Close  Up  Photography 

There  are  a  number  of  accessories  provided  for  covering  every 
possible  demand  which  may  arise  for  the  Leica  user  who  wishes  to 
use  his  camera  for  copying.  Each  copy  attachment  will  be  indi- 
vidually described  in  order  to  present  the  features  of  each  one  in 
such  a  way  that  the  Leica  worker  may  easily  make  the  proper  choice 
to  fit  any  special  requirement. 

Sliding  Focusing  Copy  Attachment 

Shortly  after  the  introduction  of  the  Model  C  Leica  with  the 
interchangeable  lens  feature  in  the  Fall  of  1930  I 
started  experimenting  with  the  use  of  various  ex- 
tension tubes  placed  between  the  camera  and  lens. 
These   extension  tubes   actually  take 
the  place  of  the  familiar  long  exten- 
sion bellows  to  be  seen  on  the  larger 
view   cameras.     My   results   for   this 
type    of    close-up    copy    work    were 
very  encouraging  and  I  saw  the  pos- 
sibility of  developing  a  new  field 
for    Leica    users.      Following    the 
work    with    the    metal    extension 
tubes  I  designed  the  first  Sliding 
Focusing  Copy  Attachment  which 
has  since  been  manufactured  and 
distributed  to  thousands   of  Leica    **™J* f^fdy) 
users  during  the  last  few  years.         sition  for  Copying 


Basically  the  Sliding  Copy  Attachment,  also  known  as  the  Fuldy 
Copy  Attachment,  consists  of  two  metal  plates,  one  for  attaching  to 
the  camera  and  the  other  for  holding  the  lens  and  extension  tubes. 
On  the  part  which  holds  the  camera  there  is  a  ground  glass  with  a 
masked  out  area  equal  to  the  size  of  the  Leica  negative.  This  ground 
glass  screen  is  in  exactly  the  same  plane  as  the  film  in  the  Leica 
camera.  Therefore  when  the  image  of  the  object  being  photographed 
is  in  sharp  focus  on  the  ground  glass  it  will  also  be  in  perfect  focus 
when  the  camera  is  moved  into  the  same  position  directly  over  the 

The  Fuldy  Copy  Attachment  has  been  designed  for  use  in  any 
position  required  for  photographing  either  horizontal  or  vertical  sub- 
jects. A  tilting  top  or  Ball  Jointed  Tripod  head  may  be  used  for 
securing  this  attachment  to  a  tripod  for  indoor  or  outdoor  use.  A 
special  bolt  can  be  secured  for  inserting  into  the  hole  of  the  Sliding 
Arm  which  is  also  used  for  holding  the  rod  of  the  illuminating 
bracket.  "When  this  bolt  is  in  position  the  Leica  or  the  copy  attach- 
ment can  easily  be  secured  in  a  horizontal  position  for  photographing 
such  objects  as  the  human  eye,  maps  on  a  wall,  or  mounted  speci- 
mens. In  fact  after  a  little  experience  with  the  Sliding  Copy  Attach- 
ment it  will  be  found  that  any  photographic  angle  may  be  quickly 

Around  the  focusing  plate  there  is  a  clip  mount  for  attaching  the 
special  magnifier  which  is  of  value  when  obtaining  extremely  critical 
focus.  Once  the  Leica  is  attached  to  the  sliding  plate  of  the  Fuldy 
accessory  it  can  readily  be  reloaded  at  any  time  without  removing 
from  this  plate.  A  Wire  Release  must  be  used  for  releasing  the 
shutter  in  order  to  avoid  any  possibility  of  jarring  the  camera  at  the 
time  of  exposure. 

Description  of  Sliding  Copy  Attachment  Parts 

The  accompanying  illustration  gives  complete  information  about  the 
various  parts  of  the  Fuldy  Copy  Attachment.  This  copy  attachment  is 
adapted  for  use  with  the  various  Leica  models  which  have  the  interchange- 
able lens  feature.  Owners  of  the  early  Model  A  Leica  can  have  their 
cameras  converted  so  that  the  lens  will  be  detachable,  for  use  on  this  at- 
tachment as  well  as  for  the  Leica  enlars-er  and 



Fig.  121     Essential  Parts  of  the  Sliding:  Focusing  Copy  Attachment 

1.  Light  shield  to  prevent  stray  light  from  entering  camera  opening  while 

2.  Threaded  opening  for  securing  the  attachment  to  a  tripod,  extension 
arm  of  the  reproduction  stand,  or  the  Sliding  Arm  for  use  with  the 
upright  pillar  of  the  Leica  enlarger. 

3.  Dove-tail  groove  into  which  the  sliding  plate  (No.  8)  moves  while  focus- 
ing and  making  exposures. 

4.  Stop  for  use  when  changing  from  focusing  to  photographing  position. 

5.  Leica  lens  screwed  into  position. 

6.  Clamping  ring  for  holding  the  Leica  camera  securely  to  the  sliding 
base  plate. 

7.  Key  for  turning  clamping  ring  (No.  6). 

8.  Sliding  base  plate  for  holding  the  Leica  camera,  focusing  ground  glass, 
and  also  the  magnifier. 

9.  Focusing  ground  glass  in  exact  plane  with  the  film  in  the  camera. 
There  is  also  a  place  to  attach  the  magnifier  when  necessary. 

10.    Space  cut  from  the  sliding  plate  (No.  8)  to  permit  the  Model  F  or  G 
Leica  camera  to  fit  properly. 

The  Fuldy  Attachment  in  Use 

The  Fuldy  device  may  be  set  up  as  follows: 

A.  Attached  to  the  Sliding  Arm  which  is  secured  to  the  upright  column 
used  for  the  Leica  enlargers. 

B.  Mounted  on  the  Collapsible  Reproduction  Stand. 

C.  Secured  to  a  ball  jointed  or  tilting  top  tripod  head  which  in  turn  is 
attached  to  a  firm  support  such  as  a  tripod. 


Before  the  set  up  is  complete  the  subject  to  be  copied  must  be  placed 
into  position  and  properly  illuminated.  Finally  the  correct  focus  is  deter- 
mined by  moving1  the  camera  close  or  away  from  the  object.  Fine  focusing 
is  obtained  by  using  the  focusing  mount  on  the  lens,  or  in  the  case  of  the 
50mm  lenses  the  lens  barrel  is  moved  back  and  forth  in  its  mount.  Once 
perfect  focus  has  been  secured  on  the  ground  glass  the  camera  is  slid  into 
position  ready  for  making  the  exposure.  Stop  the  lens  down  as  far  as 
practical  after  focusing  and  before  making  the  exposure. 

When  the  regular  50mm  Elmar  lens  is  used  on  the  Fuldy  Attachment 
directly  without  the  use  of  additional  extension  tubes  it  is  possible  to 
photograph  any  object  which  comes  within  the  maximum  area  of  15  x  20 
inches  and  a  minimum  area  of  4  x  6  inches  simply  by  moving  the  lens  mount 
in  or  out  and  setting  the  camera  in  the  proper  position.  On  account  of  the 
sliding  feature  of  the  Fuldy  Attachment  it  is  not  possible  to  collapse  the 
lens  far  enough  for  including  greater  areas  than  15  x  20  inches  without  re- 
sorting to  a  special  adjustment  which  extends  the  usefulness  of  the  attach- 
ment up  to  any  limits  including  infinity.  To  obtain  such  areas  proceed  as 

1.  Place  a  rubber  ring1   (such  as  the  ring  supplied  with  the  Micro  Ibso 
Attachment)  around  the  barrel  of  the  50mm  lens. 

2.  Slowly  push  the  lens  barrel  into  the  mount  until  the  image  is  sharply  in 
focus  on  the  ground  glass.     The  rubber  ring  will  then  be  flush  with 
the  base  of  the  lens  mount,  and  thus  mark  the  exact  position  where  the 
lens  is  in  focus.     In  this  position  the  lens  barrel  projects  into  the  at- 
tachment and  thus  prevents  the  upper  sliding  plate  from  moving. 

3.  After  exact  focus  has  been  secured  pull  out  the  lens  barrel,  slide  the 
camera  into  position,  and  push  the  lens  barrel  back  to  its  proper  posi- 
tion now  accurately  marked  by  the  thick  rubber  ring. 

This  method  of  securing  photographs  of  larger  areas  is  seldom  required 
because  the  majority  of  subjects  copied  are  much  smaller  and  may  be 
copied  in  the  regular  way  with  the  Fuldy  Copy  Attachment. 

The  Extension  Tubes 

In  order  to  secure  proper  focus  at  the  higher  magnifications  it  is 
necessary  to  move  the  Leica  lens  away  from  the  film  plane.  Instead  of 
using  a  cumbersome  bellows  similar  to  the  larger  view  cameras  for  holding 
the  lens  in  proper  position  I  designed  the  12mm,  30mm,  60mm,  and  90mm 
metal  extension  tubes  for  this  purpose.  With  such  a  set  of  tubes  together 
with  one  of  the  collapsible  50mm  lenses,  any  combination  can  be  secured 
to  obtain  the  proper  magnification  and  focus  upon  an  object  which  might 
be  as  small  as  a  pinhead.  Such  tubes  are  small  and  light  and  keep  the 
lens  in  a  rigid  position  at  all  times. 

When  the  Fuldy  Attachment  is  used  with  th~  30mm  tube  and  the  50mm 
lens  natural  size  or  1:1  pictures  may  be  made.  By  pushing  the  lens  barrel 
into  its  mount  additional  areas  may  be  covered.  The  60mm  tube  is  very 
useful  for  securing  slightly  higher  magnifications  and  also  for  use  when 
the  Fuldy  Attachment  is  used  with  the  microscope.  An  unusually  long  set 
up  of 'extension  tubes  may  be  seen  in  the  arrangement  for  insect  photog- 
raphy illustrated  in  J.  M.  Leonard's  chapter. 

The  introduction  of  the  Sliding  Focusing  Attachment  in  connection 
with  extension  tubes  of  various  lengths  greatly  increased  the  Leica's  use- 
fulness. Every  day  new  fields  are  being  reported  where  the  application 
of  these  accessories  was  at  first  found  useful  and  later  became  indis- 


1.  Twig  and  buds  of 
sugar  maple  show- 
Ing    bud     scales 
and  bud  scars. 

2.  Flower     bud     of 
flowering      d  o  g  - 

3.  Leaf  bud  of  flow- 
e  r  i  n  g    dogwood 
showing      valvate 

4.  Naked    bud    of 
wayfaring  tree. 

5.  The     leaf     scar 
covers     the    bud. 

6.  Stipule    scars    ap- 
pearing as  a  line 
encircling    the 

7.  Twig  and  buds 
of  butternut  show- 
ing   a    leaf    scar, 
bundle  scars,  and 
superposed  buds. 

8.  Collateral  buds. 

9.  Leaf  scar  and 
stipule  scars. 

10.  Pseudoterminal 
bud    and    branch 
stub    of   red   mul- 

11.  Thorn. 

12.  Stipular  spines  of 
black  locust. 

13.  Pseudoterminal 
bud    and    branch 
scar  of  basswood. 


:  11 

Fig.  122.     Twig  and  Bud  Photographs  by  Wm.  M.  Harlow 

During  the  Winter  months  the  leafless  trees  in  our  forests  or  parks 
have  very  reliable  marks  of  identification  on  their  very  "finger-tips"  or 
twigs.  Dr.  Harlow  uses  the  Sliding  Focusing  Copy  Attachment  for  secur- 
ing interesting  close-up  photographs  of  these  buds.  Here  is  a  field  of  pho- 
tography which  is  extremely  interesting  and  many  Leica  users  can  apply 
their  knowledge  of  copying  very  successfully. 


Most  of  the  information  concerning  the  use  of  these  accessories  was 
available  for  the  50mm  lenses  because  they  are  the  most  popularly  used. 
It  will  be  found  however  that  lenses  of  longer  focal  length  are  extremely 
useful  for  certain  types  of  work*  In  order  to  facilitate  and  simplify  the 
use  of  these  accessories  with  any  of  the  Leica  lenses  and  tubes  the  Editors 
now  offer  for  the  first  time  a  new  table  and  some  basic  formulas  which 
will  enable  the  average  worker  to  determine  certain  important  factors  for 
the  different  lenses  and  extension  tubes  without  resorting  to  tedious  experi- 
mental or  mathematical  work. 

The  table  given  on  pages  198,  199  was  computed  for  the  50mm  lenses 
(either  Elmar,  Hektor,  or  Summar).  This  table  should  be  consulted  not 
only  for  information  regarding  the  use  of  these  three  lenses,  but  also  as 
an  example  of  information  that  can  be  obtained  by  the  use  of  the  few  sim- 
ple formulas  which  follow. 

It  should  be  noted  that  the  figures  contained  in  this  table  referring 
to  the  depth  of  focus  are  based  upon  the  diameter  of  the  circle  of  confusion 
being  ,03mm  (approximately  1/750  of  an  inch).  This  is  the  only  part  of 
the  table  which  is  affected  by  the  size  of  the  circle  of  confusion.  Should 
a  smaller  circle  of  confusion  be  required,  or  a  larger  one  be  found  suffi- 
cient, the  data  given  in  the  table  should  not  be  used,  but  other  figures 
computed  with  the  aid  of  the  formulas  appended. 

The  135  mm  Lens  Mount 

Still  another  method  of  securing  focus  for  objects  at  any  distance  up 
to  infinity,  when  using  the  Fuldy  Attachment,  is  by  using  the  special 
135mm  lens  mount  which  is  llmm  shorter  than  the  regular  mount  for  this 
lens.  In  other  words  this  mount  is  made  to  compensate  for  the  llmm  dis- 
placement of  the  lens  in  the  Focusing  Copy  Attachment.  (This  mount  may 
be  ordered  through  any  Leica  dealer  in  the  United  States.) 

The  135mm  lens  is  easily  unscrewed  from  its  standard  mount  and 
placed  in  the  shorter  mount  for  use  on  the  Fuldy  Copy  Attachment.  With 
this  mount  in  place  the  copy  attachment  is  excellent  for  use  in  taking 
portraits  or  any  other  subject  which  can  be  focused  upon  the  ground  glass. 

The  special  135mm  mount  is  supplied  with  a  reducing  ring  for  at- 
taching the  50mm  lenses.  By  using  this  set-up  it  is  possible  to  secure  fine 
focusing  simply  by  turning  the  focusing  mount  of  the  135mm  lens  barrel. 
Additional  extension  tubes  can  be  attached  when  required  to  secure  higher 






Fig.  123  Latent  Finger  Print 
on  Black  Rubber  Surface . . . 
Gray  Finger  Print  Powder. 
Photo  by  Ira  Gullickson.  Slid- 
ing Copy  Attachment,  used 
with  30mm  tube 



Use  of  Extension  Tubes  Directly  on  the  Camera 

Without  Sliding  Focusing  Attachment 

It  is  frequently  desirable  to  use  various  Extension  Tubes  or 
their  combinations  directly  on  the  camera,  without  the  use  of  the 
Sliding  Focusing  Attachment.  This  is  quite  practicable.  The  tube 
is  simply  screwed  into  the  camera  and  the  lens  is  screwed  into  the 
tube.  Such  an  arrangement  sometimes  can  be  used  in  lieu  of  auxil- 
iary front  lenses.  The  focusing  is  then  done  to  scale.  Great  accuracy 
is  an  absolute  prerequisite  of  success. 

The  following  table  is  given  for  this  type  of  work. 

It  is  based  upon  the  diameter  of  Circle  of  Confusion  of  0.03mm. 

Since  it  is  impossible  to  compose  the  picture  on  the  film  visually 
it  is  recommended  to  use  a  plumb  weight  whenever  this  method  is 
employed.  Special  plumb-weights  are  available,  but  any  plumb- 
weight  will  be  found  to  work  as  long  as  it  will  be  made  so  that  it  will 
drop  in  a  line  with  the  optical  axis  of  the  lens. 

(without  Sliding  Focusing  Attachment)  with  ALL  50mm  Leica  Lenses: 

Elmar  f  :3.5         Hektor  f  :2.5         Summar  f  :2 

in  Milli- 



to   Lens) 

in  MM 

Depth  of  Focus 
at  f/12.5 
Nearest  Farthest 
points  in  focus 

in  Millimeters 

in  exposure) 



in  MM 

Ratio  of 
or  Magni- 







96       X144 








54       X  81 








38       X  58 








29       X  43 








20       X  30 








16       X  24 








13       X  20 








12       X  18 







11.  5x 

10       X  15 








9       X  14 








8       X  12 








7.5   X   11 








6.7    X  10 





62.9  , 



6.25  X     9-35 



Fig.  124  Photo  of  Herbarium  Sheet  by  Carl  B.  Wolf.  An  example  to 
show  the  use  of  the  Leica  Copy  Equipment  in  one  particular  photographic 

•**  :I^^^V'\*^^;¥vi^:m^\,  o?~  *~ 

-  * 

Figr,  125  Writing  Showing  Shading  Vari- 
ations in  Pen  Pressure  and  Grain  of 
Paper.  Elmar  50mm  Lens  with  Focusing 
Copy  Attachment 

Fig.  126  Copy  of  Typewriting. . . by  Ira 
Gullickson.  Pica  type,  ruled  square  on 
glass  over  typing.  Fine  detail  shows  type 
and  kind  of  paper.  Printer's  ink  in  dotted 
line  seen  as  being  different  from  typing. 
Fuldy  Copy  Attachment  with  Elmar  50mm 
lens,  30  and  60mm  tubes. 



Exposure  Factors 

For  ALL  Extension  Tubes  When  Used  With  Various  Leica  Lenses 

and  the  Sliding  Focusing  Attachment 

Tubes     Lenses: 

















































*  Special  Focusing 








*  Special  Focusing 








*  This  Extension  tube  was  originally  designed  to  permit  the  use  of  the  135mm  lenses 
in  connection  with  the  Sliding  Focusing  Attachment.  It  is  actually  a  sawed-off  135mm 
lens  mount.  The  135mm  lens  is  screwed  into  this  tube.  In  this  form  it  can  be  used 
on  the  Sliding  Focusing  Attachment  even  at  infinity:  the  calibrations  having  been  retained. 

A  special  threaded  collar  is  supplied  with  this  tube  which  permits  the  use  of  any 
other  Leica  lens.  However  lenses  other  than  135mm  cannot  be  used  for  infinity  focus  in 
connection  with  this  tube.  These  lenses  are  used  merely  for  extreme  magnifications,  in 
which  case  this  tube  becomes  a  convenient  adjustable  extension  tube. 

This  table  of  Exposure  Factors  for  all  tubes  and  all  Leica  Lenses  will 
be  found  useful  for  ascertaining*  the  correct  exposure  factors: 

1.  when  using"  extension  tubes   directly  on  the  camera   (without 
Sliding  Focusing  Attachment),  interposing  them  between  the 
camera  and  any  lens. 

2.  when  using  various   extension  tubes  or  their  combinations  _  in 
connection  with  Sliding  Focusing  Attachments  and  any  Leica 

For  the  purpose  of  exposure  factors  the  Sliding  Focusing  Attachment  is 
considered  just  as  any  other  tube  of  llmm  length.  Every  tube,  depending 
on  its  length,  has  its  own  exposure  factor,  which  is  constant  for  every  lens. 








g     g 
OJ     i 




O     02 




t— K 




















s  I 


noo£  u; 




'<**    CD  «H 

?>  bo      ^s^^^S^.S^.sS.S°^*S 

02    §     §      W    ^      W    £>      W^      W^      CO    g      «2    £      Wr°      3 

OQ          «  w  "c          S          S          S 

'S       *§       's       *§       Is       _»       5 

o         o         o         o         o         o         o 

I     fc     a      i?      »5      !5      iz: 



I  ! 

j?  a 






""?  'y   o   ^ 

C3       CG       rH  *p"i 

«    «£! 
§    §    8l 


ro    _ 

s  .S 

43      CD 






M    O 

o  o 

0    ^ 




S  s  c  B  fl  s  s  s  .s  .S  .S  .S  .S  .S  g  g 


c5    ci 

W2      02 

g  g 


C/2      02      ^  _Q 
US      £3      02 

§  g  g  S 

fa  fa  H-3  .2 

02             O 
£      03  SH 

0         rH     _p 

O      QJ     0 
fa    HH1     tQ 


H—l     W 


g      g 
O     O 

fa  fa 




a;    cu    cu 

42    42    42 


cu    cu 

42    42 
£     S 



cu    cu                                                               *2 

^^                                                                               4?    ^            1    CM 

Cd                                    4^           ^c;^3^!^ 

gg                            s        s   s  "^     ^  s          •» 

gtf               QJ              CU             •*•>      CU    'S    'S    C^l    CM    ^2    ®    ® 
j^      g.      o             42             juj    42     ^     g    rH    CM      ^    CO    CO 

C^C^5cM      CUCM^^O^^5000^005^ 

al    io 

1  1 

4  rf 



03  ^ 


S   S   S 

ri      c!      Si 

S   S 



g      g      grH^rHo0CO    o^O^O^OO^OO^ 
SS     fi!     J-<    ^    •*•*    ^                   ^^                                                        '** 

^  "1 

CM     CM     CM 

rH     rH     rH 

CM    CM 
CM    CM 



J  -§ 


•<5  <rj  *^1 

rv     rv     r^i 


fa    fa    fa    fa    fe    fa    fa    fa    fa    fe    fa"    fa    fa    fa    fa    fa 

rv,   [£4 

•5  1 


CO   CO 

co  r/  co  co  co  co  co  co  co  co  co  co  rn  r/  co  co 

r/   CO 

00     O     rH 

CM    TH 


Lfl                     CO             SO    CO    SO                     CM             rH 




c/2      CD 
CD     W2 

O    CS    00 


t*»   to 




LO                        TH 

LO            LOCO            THOSTH            COOO            TH 


t>    CO 

CO    M 

-o  5 

CD     ^ 

CM    O    TH 
t-    SO    LO 

OO    CO 

TH     CO 



CM    CM    rH    TH    r-j    rH 

CM    rH 

CO    »O    LO 
t"»    OS    rH 
rH    rH     CM 

LO    LO 
CM    C-; 


0     LO     CO      M      M 
O    CM    OO     O    O     W^WWb^b^^^^^M 


M        M 

O    0 

O    0 

3  s 

LO    OO    00 
CM    CO    O 
0    t-    CO 
CM    rH    rH 

rH    LO 
10    CM 

rH    rH 




LO             OiftO'T:lHe'3_,__,OsOOb- 



LO    """H 
LO    CO 
LO    CM 
LO    LO 

•§    o 


LO    rH    00 

as   t-   LO 

b-    CM 

TH    CM 








co   t— 

TH    LO 
LO    CM 

LO     LO 

C3    -t-> 

^  .s 

§  .s 

LO             IO                      LO             tO 
LOb-            CMLO             CMLOb-             10 


OS    rH 

M  5 

g  g 

LO    CM 



LO     O 

CO    CM    CM 

CM    rH 



CO    0    O 
to    O    CO 

fg>       l-w      t-» 

0    CO 






0    0 

o  o 

LO     O 


O    _^j 

w    2 

CO    -S 

o  LO  os 

O    LO 
LO     CM 

.^     rH 


CO    rH 


no   o 

10    CS1 

LO    LO 

52    cu 
cu    g 


fa     r-l 


1.  L  — =  Diameter  of  lens 


2.  T  =   =  Exposure  factor  (increase  of  exposure) 

0  B  — F 

3.  —  =   =  Ratio   of   reduction    (As   a    function   of   the   object 

IF  or  magnification  distance) 

0  F 

—  = —  Ratio    of   reduction    (As    a    function    of   the    image 

IF  or  magnification  distance) 

4.  F2=(D  — F)      .      (B  —  F)  =  (Relation   between    focal   length,    object 

and  image  distance) 

D  .  JF 
B  =  =  Working  distance  of  object  to  lens 

D  — F 

B  .  F 
D  =  =  Distance  of  image  to  lens 

B  — F 

5.  Depth  of  focus  at  a  given  diameter  of  Circle  of  Confusion: 

L  .  B  .  F 

A  =   =  Nearest  point  in  focus 

(L  .  F)  +C(B—  F) 
L  .  B  .  F 

Z  =  =  Farthest  point  in  focus 

(L  .  F)  —  C(B— -  F) 

Explanation  of  Symbols 

M  —  Ratio  of  Magnification 
R    —  Ratio  of  Reduction 

0  —  Size  of  Object   (linear  dimensions) 

1  —  Size  of  Image  on  film   (linear  dimensions) 
B*  —  Distance  of  Object  to  the  Lens 

D*  —  Distance  of  Image  to  Lens 
F*  —  Focal  Length  of  Lens 
f     —  Stop  of  diaphragm 

T    —  Exposure  Factor  (increase  of  exposure) 
C*  —  Diameter  of  Circle  of  Confusion 
L*  —  Diameter  of  Lens 

A*  —  Nearest  point  in  focus  when  lens  is  focused  for  B. 
Z*  —  Farthest  point  in  focus  when  lens  is  focused  for  B. 

*  It  is  important  to  express  all  units  of  length  in  the  same  system,  either  metric  or  linear 
(inches) . 

Practiced  Applications 
1.   Diameter  of  Lens  : 

(Focal  Length) 

L  = or 

f  (Lens  Stop(f)) 


What  is  the  diameter  of  the  aperture  of  a  50mm  lens  when  it  is 
stopped  down  to  f:12.5? 


L  r=  =  4mm. 




2.    Exposure  Factor: 

Increase  of  Exposure  T  =  • 


(Distance  from  lens 
to  film  plane)2 

F2  (Focal   length)2 


What  is  the  exposure  factor  for  a  90mm  tube  when  used  directly 
on  the  camera  in  connection  with  a  90mm  lens? 

[90mni  (tube)  +  90mm  lens]2 
Distance  from  lens  to  film  plane  

180  : 


90  : 

=  4x 

90 2  81.00 

3.    Eatio  of  Reduction  or  Magnification : 

Distance    from    Object    to    Lens 
Size  of  Object  O  B  —  F  less  Focal  length  of  Lens 



Focal  length  of  Lens 

Size  of  Image 

Ratio  of  Reduction  of  an  object  900mm  from  a  35mm  lens: 
900—35  865 




Focal  length  of  lens 

say  25      -f-  1 


D— F 


Distance  from  Lens 
to  Film  Plane — minus 
focal  length  of  lens 

What  is  the  ratio  of  Magnification  obtained  when  using  60  and 
90mm  extension  tubes  in  connection  with  a  73mm  lens  (tubes 
directly  on  the  camera — no  S.  F.  A.)? 

[60  +  90  +  73  (lens)]  =  D  =  223 
F  73  73  1 

=  =  = or    1  -T-  2 

D— F          223—73  150          2.06 


Fig.  127     Copy  of  Old  Mining  Shares... by  Willard  D.  Morgan.     Focusing 
Copy  Attachment  used  with  Elmar  50mm  lens 


4.   Distance  from  Lens  to  Object  or  (B) 

"     Lens  to  Film  Plane          (D) 
(knowing  one  how  to  find  the  other) 

Basic  Formula:  F    =  (D— F)  .  (B— F) 
D  X  F  B  X  F 

B  =  D  = 

D  —  F  B  — .  F 


What  is  the  distance  at  which  the  object  is  to  be  placed  when  a 
60mm  tube  and  S.  F.  A.  are  used  with  a  IS 5mm  lens? 

(135  +  60  +  11)   X  135 

B  = 

(135  +  60  +  11)  —  135 
206  X  135         27810 

=  392mm 

206  —  135  71 

What  Extension  tubes  are  to  be  used  when  a  50mm  lens  is  avail- 
able and  the  object  is  97mm  from  the  lens? 

97  X  50         4850 

D  = = =  103mm  103mm  —  50mm  lens  =  53mm 

97  _  50  47 

or  53mm  =  llmm  (S.  F.  A.)  +  12mm  (tube)  +  30mm  (tube) 

5.   Depth  of  Focus : 

The  depth  of  focus  for  any  lens  at  any  opening  or  distance  depends 
on  the  diameter  of  the  Circle  of  Confusion.    In  all  standard  Leica 
formulas  the  diameter  of  the  Circle  of  Confusion  is  taken  to  be 
C  =  0.03mm 

L  X  B  X  F 
Nearest  point  in  focus:  A  = 

(LXF)+C(B  —  F) 

L  X  B  X  F 

Farthest  point  in  focus  :  Z  =:  - 

(L  X  F)  —  C  (B  —  F) 


What  is  the  depth  of  focus  of  a  90mm  lens  at  Stop  F:  9,  focused 
upon  an  object  5  'meters  away,  assuming  the  size  of  the  C.  of  C. 
to  be  0,01mm? 


=  10mm;  B  ==  5000mm  C  =  0.01 


10  X  5000  X  90  4,500,000 

A  ==  -  •  =  -  —  =  4750mm 
(10  X  90)   +  .01  (5000  —  90)          900  +  49.10 

10  X  5000  X  90  4,500,000 

Z  =  --  =  --  =  5300mm 
(10  X  90)  —  .01  (5000  —  90)          900  —  49.10 

Depth  of  focus  will  result  in  everything  being  in  sharp  focus  at 
from  4.75  meters  to  5.30  meters. 



Avoiding  Vibration  During  Copying 

Usually  most  close-up  copy  work  requires  time  exposures  ranging1  from 
3/4  second  up  to  5  minutes  or  even  more.  During  such  exposures  there  must 
be  no  vibration  in  the  equipment  to  cause  a  blurred  image  on  the  negative. 
In  order  to  avoid  vibrations  the  following  points  should  be  observed. 

1.  Use  a  rigid  support  for  copying  equipment. 

2.  Release  shutter  with  a  Wire  Cable  Release. 

3.  In   case   you  are   working  in   a  building   which   transmits   the 
annoying  vibrations  of  passing  trains,  trucks,  or  a  subway,  a 
sponge  rubber  mat  might  be  placed  under  the  baseboard  of  the 
copying  attachment  in  order  to  absorb  the  motion. 

4.  When  all  the  extension  tubes  are  in  use  have  a  support  or  clamp 
to  hold  the  combination  rigid. 

5.  When  vibrations  cannot  be  avoided  use  more  illumination  on  the 
object,    a    larger    diaphragm    stop,    fast    film,    and    make    fast 


As  the  camera  lens  is  placed  closer  to  the  object  the  focusing  becomes 
more  critical.  Naturally  without  perfect  focus  the  object  will  be  reproduced 
on  the  negative  as  a  slight  or  even  complete  blur.  With  the  Leica  camera 
there  are  three  methods  of  obtaining  proper  focus. 

1.  By  actual  focusing  upon  a  ground  glass  in  the  Sliding  Copy 

2.  By  measurement  and  the  use  of  the  printed  tables  supplied  for 
the  purpose. 

3.  By  using  the  fixed  focus  attachments  such  as  the  Bemar,  Belun, 
Besal,  etc. 

Ground  glass  focusing  is  recommended  in  the  majority  of  cases  because 
it  is  so  easy  to  actually  see  the  object  projected  upon  the  glass  surface  which 
is  in  the  same  plane  as  the  film  in  the  camera.  A  special  5x  magnifier  is 
of  additional  help  when  determining  exact  focus  with  the  Sliding  Focusing 
Copy  Attachment.  In  case  there  is  too  much  stray  light  falling  upon  the 
ground  glass,  when  the  magnifier  is  not  in  use,  take  a  piece  of  black  paper 
about  4x6  inches  in  size  and  wrap  this  around  the  ground  glass  mount.  Use 
a  rubber  band  to  hold  the  paper  shade  in  position  around  the  base.  You  will 
now  have  a  paper  tube  which  will  keep  out  any  stray  light.  When  the 
•magnifier  is  in  position  this  paper  tube  is  not  required. 

The  ground  glass  of  the  Focusing  Copy  Attachment  looks  grainy  when 
examined  with  the  aid  of  the  5x  magnifying  glass.  Considerable  improve- 
ment of  the  clearness  of  the  image  is  obtained  by  applying  a  drop  of  oil 
(cocoanut  oil  is  very  good)  to  the  ground  surface  of  the  glass.  Rub  the  oil 
in  gently  and  evenly,  moving  the  finger  first  in  one  direction,  and  then  at 
right  angles  to  it.  This  method  will  eliminate  the  graininess  considerably 
and  increase  the  luminosity  of  the  image,  permitting  better  focusing. 

Critical  Focusing  and  the  Special  30x  Magnifying  Glass 

A  special  30x  magnifier  is  available  to  secure  critical  focus  for  those 
who  require  the  utmost  precision  and  accuracy.  This  magnifier  consists  of 
a  small  eyepiece  equipped  with  a  tiny  lens  of  the  microscope  ocular  type 
and  Quality.  The  lens  with  its  mount  slides  in  a  collar  which  fits  into  the 
half-rim  clip  on  the  ground  glass  of  the  Focusing  Copy  Attachment.  This 
magnifier  cannot  be  used  with  the  regular  ground  glass  supplied  with  the 


Fuldy  Copy  Attachment,  be  It  ever  so  fine-grained.  It  would  only  magnify 
the  grain  30  times,  but  would  not  resolve  the  details  of  the  image  focused 
upon  the  surface. 

A  special  ground  glass  is  available  for  use  with  this  30x  magnifier. 
It  has  a  narrow  strip  of  clear  glass  running  across  the  center  of  the  disc. 
This  clear  strip  is  about  3mm  wide.  A  millimeter  scale  is  engraved  in 
finest  hairlines  upon  the  ground  side  of  the  glass  disc,  which  corresponds  to 
the  film  plane  in  the  Leica  camera.  The  scale  starts  with  0  in  the  center 
of.  the  disc  and  continues  to  the  right  and  to  the  left  of  the  0  in  millimeter 

The  magnifier  is  placed  upon  the  Copy  Attachment  just  like  the  regular 
5x  magnifier.  The  eyepiece  is  then  moved  in  or  out  until  the  scale  en- 
graved upon  the  glass  appears  in  perfect  focus,  sharp  and  clear.  Then  the 
object  or  the  camera  is  moved  until  the  small  portion  of  the  object  seen 
through  the  magnifier  appears  in  sharp  focus.  It  will  be  found  that  the 
image  is  clear  and  brilliant  and  permits  the  finest  hairline  adjustment. 

This  30x  magnifier  works  upon  the  principle  of  picking  up  the  mag- 
nified image  of  the  object  from  the  air.  The  focal  point  of  the  lens  of  this 
magnifier  is  so  critical,  that  if  the  image  is  not  exactly  in  the  film  plane,  it 
will  appear  unsharp  until  corrected.  The  focusing  should  be  done  with  the 
lens  of  the  camera  open  enough  to  permit  sufficient  illumination  to  enter  for 
easy  focusing.  After  correct  focus  has  been  secured,  reduce  the  lens  dia- 
phragm to  the  desired  stop. 

Coarse  focusing,  or  the  preliminary  work  in  bringing  the  object  into 
fairly  accurate  focus  upon,  the  ground  glass,  is  secured  by  placing  the 
camera  closer  or  farther  away  from  the  object.  In  doing  this  the  Sliding 
Arm  to  which  the  camera  and  Copy  Attachment  are  secured  is  raised  or 
lowered  on  the  metal  upright  bar  which  supports  the  equipment.  In  case 
the  camera  is  in  the  horizontal  position  mounted  on  the  Sliding  Arm  or  on 
a  tripod  it  is  only  necessary  to  move  either  the  object  or  the  camera  closer 
or  farther  away  until  sharp  focus  is  secured. 

When  using  a  50mm  dens,  fine  focusing  can  be  secured  by  turning  the 
lens  mount  or  by  slowly  pushing  the  lens  barrel  in  or  out  of  the  mount. 
If  the  90mm  or  any  other  lens  besides  the  50mm  lenses  are  used  the  fine 
focusing  is  easily  secured  by  slowly  turning  the  focusing  mount  on  each  lens 
until  sharp  focus  is  secured. 

When  working  with  small  objects  a  convenient  stage  or  mount  can  be 
made  with  an  adjustable  rack  and  pinion  arrangement  similar  to  the  stage 
of  a  microscope.  Sometimes  such  a  stage  can  be  picked  up  in  a  second 
hand  store  for  only  a  few  dollars;  it  makes  a  perfect  platform  for  adjusting 
small  objects.  Such  a  stage  is  fully  described  in  the  chapter  by  J.  M. 
Leonard  on  photographing  insects. 

Focusing  by  Measurement 

When  the  Leiea  is  to  be  used  without  the  aid  of  additional  copy  at- 
tachments accurate  focusing  may  be  secured  by  referring  to  the  special 
booklet  of  tables  for  the  Front  Lenses,  which  is  available  free  for  any 
Leica  owners  who  use  the  Front  Lenses  in  copying.  This  booklet  of  tables 
gives  the  exact  distance  between  the  object  and  the  film  of  the  camera  (not 
the  lens),  the  exact  area  covered  by  either  one  of  the  three  supplementary 
Front  Lenses  used,  and  also  the  depth  of  focus  at  the  various  diaphragm 

When  using  the  Leica  with  the  Front  Lenses  it  is  necessary  to  have 
the  camera  secured  to  the  Sliding  Arm  or  to  a  tripod  or  any  other  fixed 
support,  in  order  to  keep  the  camera  perfectly  rigid. 



Still  another  method  of  focusing  by  measurement  is  with  the  use  of 
the  various  Extension  Tubes  directly  on  the  camera.  When  these  tubes  are 
used  singly  or  in  combination  it  is  not  necessary  to  use  the  three  Front 
Lenses  already  mentioned.  The  Extension  Tubes  will  enable  you  to  use  the 
Leica  at  closer  distances.  For  those  who  wish  to  use  the  Leica  for  copying 
without  the  use  of  any  copy  attachment,  a  measurement  table  for  use  with 
the  Extension  Tubes  screwed  directly  into  the  camera  has  been  prepared  by 
Mr.  Lester.  The  Single  Exposure  Leica,  described  in  the  first  chapter,  can 
be  used  very  successfully  for  testing  these  fixed  distances. 

A  special  copying  baseboard  can  easily  be  prepared  to  include  the 
various  areas  given  in  the  table  by  marking  out  the  rectangular  areas  in 
ink  or  cut  lines  in  the  wood.  Each  rectangle  should  have  figures  giving 
the  area  and  also  the  Extension  Tube  and  lens  setting  required  to  secure 
perfect  focus.  Such  a  ruled  board  will  be  of  great  convenience  for  use 
where  many  pictures  are  to  be  made  of  objects  which  are  fairly  uniform  in 
Stopping  Down  the  Lens 

All  copying  should  be  done  with  the  lens  stopped  down  to  f:6.3  or 
smaller  if  possible.  As  the  lens  is  stopped  down  the  depth  of  focus  in- 
creases, thus  insuring  perfect  focus  at  all  times  even  if  a  slight  miscalcula- 
tion has  been  made  when  securing  the  original  focus.  When  working  with 
high  magnifications  the  lens  should  always  be  stopped  down  to  f  :12.5.  A 
special  diaphragm  Attachment  Ring  is  available  for  use  with  the  Hektor 
and  Elmar  50mm  lenses,  in  order  to  adjust  the  diaphragm  with  side  cali- 
brations and  thus  avoid  the  necessity  of  standing  on  one's  head  to  read  the 
settings  on  the  face  of  the  lens  in  case  it  is  pointing;  down  toward  an 

Fig.  128     Sea  Urchin  (Original  Specimen  1%  inches  diameter).     Series  of 
Four  Pictures  by  Willard  D.  Morgan 

Photographs   made  with  Focusing  Copy   Attachment  and   various   extension   tubes  to   secure 
different  magnifications.     Highest  magnification  made  with  a  21   cm  tube  extension. 


Fixed  Focusing 

The  various  fixed  focus  attachments  such  as  the  Belun,  Behoo,  and 
Bazoo  are  of  value  for  certain  uses  and  when  only  a  few  areas  are  to  be 
covered.  The  Belun  attachment  is  permanently  in  focus  for  making;  pictures 
the  exact  size  of  the  Leica  negative  or  a  1:1  ratio.  The  Behoo  and  Bazoo 
have  extension  legs  with  markings  for  special  settings  and  areas  covered. 
Complete  information  about  these  attachments  will  be  found  in  a  special 
booklet  from  the  Leitz  Company. 

Securing  Proper  Illumination 

The  importance  of  proper  illumination  of  objects  to  be*  photo- 
graphed at  close  range  cannot  be  over-emphasized.  Objects  can  be 
flooded  with  strong  light  until  they  become  flat,  lifeless,  and  washed- 
out  reproductions  on  the  negative.  However  with  the  proper  type 
of  lighting  the  very  same  objects  will  take  on  a  richness  of  tone 
value  which  makes  the  final  picture  strong  and  at  the  same  time  a 
perfect  reproduction  of  the  original. 

One  of  the  first  methods  of  checking  proper  lighting  is  by  per- 
sonal observation.  Side,  top,  or  back  lights  may  be  adjusted  at 
various  distances  from  the  object,  diffusion  screens  can  be  used  to 
soften  strong  direct  light  rays,  high  01?  low  power  bulbs  should  be 
used  when  necessary.  In  some  cases  it  may  even  be  necessary  to  set 
up  one  or  more  flash  bulbs  for  making  the  picture.  In  most  cases  the 
lights  can  be  adjusted  visually. 

The  best  way  to  check  the  intensity  of  the  illumination  over  an 
object  such  as  a  manuscript  page,  is  by  using  an  exposure  meter. 
When  in  doubt  about  the  proper  balancing  of  the  lights  this  meter 
provides  a  rapid  means  of  cheeking. 

For  the  majority  of  objects  the  ordinary  side  lighting  with  the 
lights  set  at  a  45°  angle  is  sufficient.  One  or  two  lights  are  placed  on 
each  side,  depending  upon  the  size  of  the  object.  When  these  lights 
are  placed  at  a  45°  angle  the  strong  light  rays  illuminate  the  area  to 
be  photographed  without  causing  back  reflections  which  would  ruin 
the  picture,  or  at  least  make  it  fall  short  of  becoming  a  perfectly 
illuminated  reproduction. 

A  convenient  lighting  set-up  consists  of  two  ordinary  desk  lamps 
with  reflectors.  Two  frosted  75-watt  bulbs  are  sufficient  for  illumi- 
nating all  areas  up  to  12  x  16  inches.  Beyond  -this  area  use  four  or 
more  lamps  as  required.  Even  such  a  rule  may  not  hold  for  every 
set-up,  because  it  is  possible  to  use  two  photo-flood  lamps  or  two  500- 
watt  lamps  in  reflectors  and  evenly  illuminate  greater  areas.  If  you 
have  a  Kodalite,  Solite,  or  similar  lighting  outfits  they  can  be  used 
very  successfully  for  copying.  Usually  the  high  power  bulbs  must 



be  replaced  with  globes  of  lower  light  intensity  in  order  to  avoid  over- 

It  is  also  possible  to  nse  normal  daylight  when  convenient,  al- 
though artificial  lighting  is  more  constant  and  easier  to  control. 
Sometimes  when  copying  in  libraries  it  is  not  possible  to  carry  in 
extra  equipment  such  as  lights.  Here  is  where  it  is  necessary  to  use 
natural  daylight.  When  photographing  under  such  conditions  the 
full  illumination  from  a  window  is  sufficient.  Avoid  any  cross  light- 
ing from  other  windows  which  may  cast  shadows  or  otherwise  cause 
uneven  illumination. 

Strong  lights  are  useful  when  photographing  moving  subjects 
where  short  exposures  are  required.  In  some  cases  the  strong  lights 
may  cause  too  much  heat  or  otherwise  disturb  the  subjects.  To  avoid 
this  the  focusing  may  be  done  with  a  small  light,  then  when  the  ex- 
posure is  to  be  made  the  full  illumination  is  snapped  on  just  before 
the  shutter  is  released.  It  may  also  be  advisable  to  use  stronger 
lights  when  heavy  color  correction  filters  are  used,  thus  reducing  long 

Lighting  Medical  Specimens 

Macro  photography  of  gross  specimens  is  a  term  often  heard 
when  referring  to  the  copying  of  medical  objects  such  as  bone  sec- 
tions, animal  or  human  organs,  or  sections  of  tissues.  Here  is  where 
a  knowledge  of  lighting  is  of  special  importance  in  order  to  obtain 
good  detail  in  the  objects  and  also  avoid  glistening  high  lights  or  bad 
reflections.  In  some  cases  the  objects  can  be  placed  under  water  in 
a  large  glass  specimen  jar,  with  the  light  directed  from  the  sides. 
Annoying  reflections  are  thus  avoided. 

When  a  medical  or  any  other  subject  is  to  be  reproduced  with 
a  plain  white  background  there  are  three  ways  to  do  this. 

1.  Make  the  photographs  and  then  opaque  the  negative  by  painting 
around  the  object  with  opaque  paint. 

2.  By  using  a  white  surface  as  a  background  for  the  object. 

3.  Produce  a  strong  back  lighting  through  an  opal  or  ground  glass. 
Such  a  backlight  will  overexpose  the  background  around  the  ob- 
ject.   The  specimen  is  illuminated  from  the  top  in  the  usual  way. 
When  the  paper  enlargement  is  made  from  this  negative  the 
background  will  reproduce  perfectly  white  if  the  exposure  is  made 
for  the  object  only.    • 

One  of  the  most  useful  accessories  for  copy  work  is  an  illuminated 
light  box.  With  such  a  box  the  under  or  back  lighting  is  easily 
controlled,  because  the  lights  may  be  switched  on  for  only  part  of 


the  time  while  the  exposure  is  being  made  for  the  specimen  mounted 
on  top  of  the  ground  glass.  Such  a  lighting  also  helps  to  eliminate 
unnecessary  shadows  when  necessary.  The  top  lights  are  used  for 
illuminating  the  object. 

When  a  jet  black  background  is  required  for  a  light  object  It 
may  be  obtained  by  using  a  red  glass,  or  celluloid,  or  paper,  in  the 
illuminated  box  providing  positive  or  orthochromatic  film  is  used 
in  the  camera.  The  red  does  not  register  on  this  film,  therefore  when 
the  finished  enlargement  is  made  a  rich  black  is  secured  for  the 
background.  Black  paper  or  cloth  may  also  be  used  for  a  similar 

Still  another  lighting  set-up  which  produces  a  white  background 
without  shadows  can  be  prepared  by  mounting  a  clear  pane  of  glass 
about  six  inches  or  more  above  a  plain  white  surface  which  is  strongly 
illuminated.  By  arranging  the  top  lights  at  the  proper  angles  the 
shadows  are  cast  out  of  photographing  range  while  the  illuminated 
white  surface  produces  an  even  background.  This  arrangement  is  of 
value  for  photographing  many  objects  besides  medical  specimens. 

Fig.  129  Focusing 
Copy  Attachment  Set- 
up with  Illuminated 
Light  Box  for  Copy- 
ing X-rays,  and  Ob- 
jects which  Require 
an  Illuminated  Back- 



Exposure  Time  in  Copying 

As  the  camera  is  placed  closer  to  objects  and  the  lens  Is  separated 
farther  from  the  film  plane,  the  relative  exposure  time  increases.  Con- 
sequently^ the  values  of  the  diaphragm  stops  vary  according  to  the  degree 
of  reduction  or  magnification.  For  example,  when  photographing  objects 
in  actual  size  on  the  Leica  negative  the  diaphragm  of  the  50mm  lens  will 
be  lOOmni  from  the  film  plane.  In  other  words,  when  photographing  objects 
actual  size  on  the  Leica  negative  the  distance  between  the  nodal  plane  of 
the  lens  and  the  film  must  be  twice  as  great  as  the  focal  length  of  the 
lens.  With  such  varying  conditions  the  actual  value  of  the  stop  changes, 
with  the  resulting  changes  in  exposures.  Once  the  correct  exposure  for  a 
given  distance  has  been  determined  the  exact  factors  for  exposures  at  dif- 
ferent settings  may  easily  be  determined  by  referring  to  the  tables. 

The  following  six  points  must  be  observed  before  determining  the 
exact  exposure  time: 

1.  Intensity  of  the  light  used. 

2.  Diaphragm  stop  to  be  used. 
3'.    Speed  of  the  film. 

4.  Multiplying  factors  of  any  filters  used. 

5.  Character  of  the  object  to  be  copied,  which  may  be  dark  or  light,  rough 
or  smooth. 

6.  The  distance  between  the  lens  and  the  film,  which  determines  the  ex- 
posure factor  for  reduction  or  enlargement  as  given  on  page  198. 

When  photo  graphing  very  small  objects  it  will  be  found  that  it  is  dif- 
ficult if  not  impossible  to  get  a  reading  on  the  exposure  meter,  which 
will  be  correct.  This  is  due  to  the  fact  that  the  average  meter  usually 
covers  a  much  greater  field  than  that  occupied  by  the  object.  It  will  be 
found  helpful  to  get  a  piece  of  paper  of  about  5x7  inches  or  some  other 
material  of  a  brightness  or  color  similar  to  that  of  the  average  color  or 
brightness  of  the  object  and  get  a  reading  on  that  by  placing  it  approxi- 
mately in  the  plane  of  the  object  with  relation  to  the  light  source.  In  the 
case  of  insects  or  similar  small  objects  it  will  be  found  most  expedient  to 
color  a  piece  of  paper  with  water  colors,  giving  it  the  average  tint  of  the 
texture  of  the  insect. 

The  most  accurate  method  of  determining  exposures  when  copying1  is 
to  make  actual  test  pictures  with  different  exposure  times.  A  short  length 
of  film  may  be  placed  in  the  Leica  magazine  and  exposed  under  varying, 
lighting,  filter,  diaphragm,  and  magnification  or  reduction  conditions.  De- 
velop this  film  the  proper  time  and  then  study  the  results  and  determine 
the  exact  exposures  to  be  given  on  the  next  roll  of  film  which  will  be  ex- 
posed under  the  correct  requirements. 

Even  a  single  exposure  can  be  made  on  a  short  piece  of  film  inserted 
directly  into  the  Leica  after  the  Film  Magazine  and  Take-Up  Spool  have 
been  removed.  To  do  this,  cut  a  piece  of  film  approximately  four  inches 
in  length  and  insert  directly  into  the  camera  back  of  the  shutter.  Press 
one  end  down  ahead  of  the  other  to  avoid  catching  the  film  edge  on  the 
lower  metal  frame  which  determines  the  margin  along  one  side  of  the 
negative.  Try  loading  in  daylight  first,  the  exact  position  of  the  film 
will  be  quickly  seen  if  the  focal  plane  shutter  is  set  at  Time  and  held  open. 
As  35mm  film  is  inexpensive  this  method  of  testing  exposures  will  be  a  real 
time  saver  and  also  help'  produce  perfectly  exposed  negatives  when  the 
good  roll  of  film  is  used. 


The  Single  Exposure  Leica,  described  in  the  first  chapter,  can  also  be 
used  for  making  single  negative  tests.  In  addition  to  this  camera  there 
is  a  convenient  single  exposure  film  holder  for  use  directly  in  the  regular 
Leica  camera. 

Always  keep  accurate  written  records  of  exposures  and  notes  about 
filters,  diaphragm  stops,  illumination,  etc.,  when  copying.  After  each  roll 
of  film  is  developed,  mark  the  perfect  exposures  in  your  record.  Then 
after  a  number  of  rolls  have  been  exposed  and  recorded  a  final  master 
exposure  table  should  be  made  for  future  reference. 

Films  Used  in  Copying 

When  selecting  a  film  for  copy  work  it  is  very  important  to  have 
a  thorough  understanding  about  the  various  film  emulsions  and  just 
what  to  expect  from  each  one  used.  You  may  have  attempted  to 
copy  a  book  page  or  an  article  from  your  daily  newspaper  with  one 
of  the  fast  panchromatic  films  and  then  wondered  why  the  finished 
negative  looked  flat  without  much  contrast  after  development.  Or 
you  may  have  copied  an  original  photograph  with  a  slow  positive 
film  and  wondered  why  some  of  the  shadows  disappeared  and  Tbe- 
came  black  blotches  in  the  negative  or  final  enlargement. 

Films  for  copy  work  may  be  roughly  divided  into  four  main 
classes  as  follows: 

1.  Slow  positive  films. 

2.  Slow  panchromatic  films  such  as  Micropan,  Panatomic,  Finopan, 

3.  Orthochromatic  films. 

4.  Fast  Panchromatic  films. 

Positive  film  is  contrasty  and  has  an  extremely  fine  grain  emulsion. 
This  film  obtains  its  name  from  the  fact  that  it  is  used  in  the  motion 
picture  industry  for  making  positive  prints  from  original  negatives 
for  projection.  Likewise  this  film  is  best  for  making  positive  prints 
for  projection  in  the  Leica  projectors.  As  positive  film  is  not  sensi- 
tive to  any  color  except  blue  and  violet,  it  should  not  be  used  when 
copying  colored  objects  when  correction  filters  are  to  be  used.  Use 
Dupont  Micropan  for  this  purpose. 

Use  positive  film  for  copying  .  .  .  printed  matter  such  as  books,  news- 
papers, charts,  maps,  line  drawings,  and  objects  which  may  require  extreme 
contrast  in  the  final  negative  and  enlargement.  As  positive  film  is  not 
sensitive  to  red  this  color  will  not  register  and  thus  there  will  be  a  clear 
portion  on  the  negative  which  prints  black  when  enlarged.  This  film  char- 
acteristic can  be  put  to  excellent  use  when  copying  maps  with  red  and 
black  lines,  stamps  printed  in  various  red  shades,  or  any  other  subjects 
where  the  red  lines  should  appear  black  in  the  finished  paper  reproduction. 
A  filter  is  not  required  for  this  type  of  work,  just  use  the  positive  film  for 
making  the  negatives  in  the  Leica,  and  make  the  exposures  in  the  usual 



Use  the  slow  panchromatic  films  such  as  Micropari  for  copying  .  ,  . 
multi-colored  printed  matter,  blue  prints,  or  whenever  correction  filters 
are  to  be  used  for  obtaining  special  effects  or  more  contrasty  results. 
For  example  a  snappy  black  and  white  reproduction  may  be  required  from 
an  old  newspaper  yellowed  with  age.  How  can  we  obtain  the  proper  re- 
sults? To  do  this  simply  use  Micropan  film  with  a  number  II  or  III 
yellow  filter.  In  case  still  more  contrast  is  required  use  a  Wratten  G  or 
even  a  light  red  (A)  filter. 

When  copying1  a  miscellaneous  collection  of  subjects  which  may  re- 
quire some  color  correction  along  with  others  which  do  not  require  any 
Micropan  film  is  recommended  as  the  most  practical  film  for  all  around 
use.  This  film  can  be  used  without  filters  for  the  ordinary  black  and 
white  copying. 

Use  the  orthochromatic  films  for  copying  .  .  .  original  photographs 
and  objects  where  a  better  gradation  of  values  must  be  secured  in  the 
final  reproduction.  The  orthochromatic  films  are  fine  grained  and  are  not 
as  contrasty  as  the  positive  emulsions.  In  case  positive  film  is  not  avail- 
able it  is  possible  to  use  one  of  the  orthochromatic  films  for  copying  printed 
matter  and  secure  pretty  good  results,  provided  a  contrast  developer  is 
used.  The  Perutz  Fine  Grain  Film  is  very  good  for  this  type  of  work 
while  the  Agfa  Plenachrome,  Gevaert  Superchcrome,  and  others  can  also 
be  used. 

Use  the  fast  panchromatic  films  for  copying  .  .  .  paintings,  moving 
objects  which  require  fast  films,  and  any  subjects  which  require  color  cor- 
rection filters  and  short  exposures  at  the  same  time.  This  film  gives  more 
latitude,  or  in  other  words  there  is  more  gradation  of  values  between  the 
highlights  and  shadows,  this  is  of  special  value  when  copying  paintings 
which  require  faithful  reproduction  of  the  delicate  color  gradations. 

Developing  Films  in  Copy  Work 

Copy  films  are  developed  according  to  the  results  required  just  as 
the  proper  film  is  selected  for  obtaining  definite  results.  The  usual  tech- 
nique which  is  fully  explained  in  the  chapter  on  developing  applies  equally 
well  to  the  processing  of  copy  films.  The  only  important  variation  conies 
when  developing  the  positive  or  the  Micropan  films  where  greater  contrast 
is  required  and  development  can  be  prolonged  if  necessary. 

After  printed  matter  or  similar  subjects  have  been  copied  on  posi- 
tive film  one  of  the  developers  to  use  in  finishing  the  negative  is  the  East- 
man D-ll  solution  which  is  mixed  as  follows: 

Contrast  Developer  (D-ll) 

Water   (about  125°   F.) 16  ounces  500  cc 

Elon   (Metol,  Pictol,  etc.) 15  grains  1  gram 

Sodium  Sulphite 2l/2  ounces  75  grams 

Hydroquinone    130  grains  9  grams 

Potassium  Carbonate  'or   Sodium   Carbonate..  360  grains  25  grams 

Potassium  Bromide 70  grains  5  grams 

Cold  water  to  make    32  ounces  1  liter 

This  fornrala  used  at  65°  will  give  very  good  contrast  in  five  minutes.  When  less  con- 
trast is  desired,  the  developer  should  be  diluted  with  an!  volume  of  water. 

Development  of  the  positive  film  should  be  carried  out  for  the  full 
time.  If  the  negative  becomes  too  dense  during  this  developing  time  it 
means  that  too  much  exposure  has  been  given  when  copying  the  original 
subject.  Only  the  finest  negatives  result  from  perfect  exposures  and  com- 
plete development.  Of  course  one  can  watch  the  development  of  positive 


film  under  a  red  safelight  and  slightly  underdevelop  the  film  if  it  is  seen 
that  the  exposures  were  too  heavy.  However  the  finished  enlargements 
from  such  negatives  will  not  have  the  snappy  quality  which  can  be  secured 
by  full  development  of  a  perfectly  exposed  negative. 

In  case  extremely  contrasty  results  are  required  on  positive  film  a 
caustic  developer  such  as  the  Eastman  D-9  will  produce  the  correct  results. 

Caustic  Process  Developer  (D-9) 

Stock  Solution  A 

Water  (about  125°  F.) 16      ounces          500      cc 

Sodium  Bisulphite    %  ounce  22 1/2  grams 

Hydroquinone  %  ounce  22 1/2  grams 

Potassium  Bromide    %  ounce  22i/2  grams 

Cold  water  to  make 32     ounces  1      liter 

Stock  Solution  B 

Cold  water   32      ounces  1      liter 

Sodium  Hydroxide  (Caustic 
Soda)    1%  ounces  52  l/z  grams 

Use  equal  parts  of  A  and  B  and  develop  about  three  minutes  at  65°  F. 
Cold  water  should  always  be  used  when  dissolving  Caustic  Soda  because 
considerable  heat  is  evolved.  Solution  A  should  be  stirred  thoroughly 
when  the  caustic  alkali  is  added,  otherwise  the  heavy  caustic  solution  will 
sink  to  the  bottom. 

This  developer  oxidizes  quite  rapidly  and  cannot  be  used  over  again 
after  the  first  developing.  Therefore  it  is  best  to  make  several  short  test 

,  a'w'liJ:»S!iff 

iirw  od  i^"3}?            •         UttttTersity  of  Afisotta                               oms«orTH«i*«Hn*Ai* 



ABHirrto    3f   1.  1*5,  1385      Fnn«Bi«3he«  Iii&H  3v3JOOiwirM  yW5hr*a       •TANDit.oiNTueem.teoEai'     V»«i« 

M»JOPt  SUBJECT  .>Ut,li  '     itfh.*.!    tiltS  tl.  AWARCCO    THE 


!rrKwr:  ,    w.OT^Tn^w..«     ;•; 




««»««*«»     '            ,W,,PI,v»Tmtcf,olW,               £ 


tel"  ft* 



1  nwie     ?a      JUto-y  3f  toflie                      8 


"i«i  w  T^n^r™ 

**l«*'0  Wa>- 

V  <UV* 


"•        lOSB 

*ar  Twdni?)-.-  &  3t^W  diw. 

j                       0.iiver»ity  of  $?&a!iingt<m  1930 


Music    7of4  yiAno                                      fi 


i      w        76      I-rlaary  Wsle                          S 

i  .r.    i«ih 

j.sst  .Yr.f'nj.a!  c&l  iaauatiar. 

"       7?      intenaediatft  Muaio                2 

"l«lc  l\ 


78      i»eci»iJary  Sc&aol  *tu«!o          2 







"           lOfi  i    COOpOSltlOJl   I                                      J? 

1  £.t&$e»    08      Secondary  Educwtioa               K 
See.    81        rivtrotmction  to  Sociology    3  : 



-   -  —  ^ 

BNf«\Nl  8  (  Slims  MCUJ! 

11      Wed 

Voice                                          1 

1  Muaio  4ah    '  Kamoj.y  TI                                3  t/3 
.      »      l?a      imllv{4ua2,  Saud  r«wt«i.        1 
[      *       57<2      Voic«                                           i 

(J  *""'"•'*    '  4  ',,,""„*'* 

M,tS,     87»h 

J.i-v*>y  'tf  KjfjliHls  Lit.           S 

tussle              H*etiw  Credit                        2 


£!£             Tsr^S 

fiji.  ??J.  ^'S'SJiS  *""""**  Un  4 

I"'                                                                                            .                                    ?" 



"^'S-"-  .  "  *  ~^\^ 


i!u*ne  li'iVd 

?T  wfT^n'o^                    ^i 
^•MNil  iJ^-h«la*                 ^|[ 



fcda«,  14, 


tu'n.,1    i  is^ 

;  —  ri 

"      iSm 

Frit?  ijftw  of  )i-J.%«BMng  {8J 


;,:::  .  j"^;fg~T 

JAi»t««  U4B 

tocl»«trfitioa  I                      s 

"       24& 

String  iAsslrustoci!  OJCHU          1 

__L»UA  __„        -    ... 

Violin                                         1' 


Voice                                          J! 

,        oi  tUswoom  w« 

^a^wt^i^S^J?^^^'^^          '  B"*Irfl)<' 

a  wntwtw  of  IS  wwKs.  and  a-wumrs  3  Jwura  ot  pofpuralfon;  it  may  wswl  for  t  fan 

\Wntiwrto4  11 

tMriwaf               '    '        '              i*1**        *           *nti«««v  «r«  k,    tic 

-Jnwoipfett,    IKowirtwn  to  Iw  nwd«  up  by  *stra  tlsw  wwfe  orV  <^»mIiM<5o 

TfUANSCKirT  TEC     rtrstwtiyof  iwordfumMwi  *«!««,«  c!,anjrf»t,t!r!oii«I(fl|»M$I  <•«!< 

Fig.  ISO    Copy  of  Student  Record  C.  Zaner  Lesher 

An  Example  to  Show  How  the  Copy  Equipment  can  be  Used  for  Saving 
Considerable  Time  in  Copying  all  Types  of  Eecords. 


Fig.  131  Orange  Stamp  with  Bla  k  Sur- 
charge..  .Green  Filter  used  to  Giv  Better 
Black  and  White  Contrast. 

Fig.  132  Same  Stamp  as  Fig.  131.  Red 
,(F)  Filter  Used  to  Absorb  Orange  Color 
:»f  Original  Stamp,  Permitting  only  Black 
.Surcharge  to  Register. 

Fig.  133  Genuine  Stamp.  Note  the  Clear 
Design  of  this  Stamp  as  Compared  to  the 
Forgery  Shown  in  Fig.  136. 

Fig.  134  Detail  of  Genuine  Stamp.  Note 
Clear  Detail  and  Individual  Parts  which 
Differ  From  Forged  Stamp  Shown  in  Fig. 
135.  The  Second  Ray  to  the  Left  of  the 
Sprout  Almost  Touches  the  Ground. 

Fig.    135     Detail   of   Forged   Stamp.      Note 

that  the   printing   is   not   as   Clear   as   the 

Genuine.     The  Second  Ray  to  the  Left  of 

the  Sprout  Coming  Out  of  the  Ground  is  Fig.  136     Forged    Stamp.      A    recent    at- 

Farther  Away  from  the  Ground.  tempt    to     copy    original    Latvia     Stamp. 

Photographs  made  by  Willard  D.  Morgan... using  Focusing  Copy 
Attachment  with  3  cm  Extension  Tube  for  full  size  stamps  and  9  cm 
tube  for  magnifications. 


strips  or  even  single  negatives  of  the  copy  material  and  develop  in  a  small 
tray  in  order  to  determine  the  exact  exposures  before  putting  through  the 
full  Leica  film  roll.  Two  rolls  of  positive  film  can  be  wound  into  the 
Correx  developing  tank  back  to  back  and  developed  at  one  time  if  neces- 
sary, if  the  operator  has  sufficient  skill  in  handling  film  in  this  manner. 

Filters  Used  in  Copying 

For  most  copy  work  only  two  or  three  filters  will  be  required. 
Even  then  a  considerable  amount  of  copying  may  be  done  without 
filters.  The  chapter  on  filters  will  give  complete  information;  how- 
ever a  few  examples  where  filters  may  be  used  with  panchromatic 
films  in  copying  may  be  tabulated  as  follows : 

1.  Wratten  G  filter    .    .    .    used  for  copying  printed  matter  on  yellowed 
paper  in  order  to  produce  a  clear  black  and  white  reproduction. 

2.  Yellow  number  II  or  III  filters   .   .   .  when  copying  paintings  to  secure 
proper  balance  of  color  values   in  the  black   and  white  reproduction. 
Colored  maps  may  require  one  of  these  filters  to  bring  out  the  proper 
legibility.     For  example  the  names  of  cities  may  be  printed  in  black 
over  a  light  red  or  orange  background.     With  ordinary  positive  film 
the  color  would  turn  dark  and  the  contrast  would  not  be  sufficient.    How- 
ever, by  using  the  yellow  filter  the  "background  is  kept  lighter  so  that 
the  names  are  readable,  and  yet  there  is  a  suggestion  of  the  shaded 
area.    In  case  the  red  background  is  to  be  eliminated  entirely  use  one  of 
the  red  filters. 

3.  Wratten  A  (red)  or  similar  filters   .   .   .   excellent  for  use  when  copying 
blue  prints  to  make  the  blue  background  reproduce  black  on  the  final 
enlargement.    Blue  or  violet  typewriting  reproduces  black  when  the  red 
filter  is  used.    This  filter  may  be  used  in  many  ways  for  securing  spe- 
cial results.    For  example  the  red  design  of  a  postage  stamp  will  dis- 
appear entirely  when  this  filter  is  used,  thus  leaving  a  black  surcharge 
in  bold  relief  for  special  study. 

The  tri-color  set  of  filters,  Wratten  A  (red),  B  (green),  and  C5 
(blue),  is  very  useful  for  securing  over  corrected  negatives  when 
certain  results  are  to  be  obtained.  When  the  colored  object  is  viewed 
through  a  filter  it  is  possible  to  obtain  some  idea  about  the  final 
result.  The  eye  looks  upon  objects  and  determines  the  differences 
either  by  the  contrast  in  colors  or  contrast  in  dark  and  light.  Nat- 
urally the  reproduction  of  dark  and  light  on  the  photographic  film 
creates  new  difficulties,  and  it  is  sometimes  better  to  over  correct  one 
color  to  get  the  proper  contrast. 

A  simple  rule  to  follow  when  using  the  tri-color  filters  is  to  use 
the  filter  which  absorbs  the  color  which  is  to  be  reproduced  as  black. 
Thus  if  the  green  (B)  filter  is  used  for  copying  a  map  printed  in 
red  lines  or  red  typewriting,  the  result  will  be  black  lines  or  type- 
written letters  on  the  white  paper.  In  case  a  red  filter  was  used  the 
red  typewriting  would  be  entirely  eliminated  and  only  a  white  blank 



sheet  of  paper  reproduced.  There  will  be  colored  objects  which  re- 
quire certain  compromises  when  using  filters  to  show  contrast  or 
gradation  and  detail  as  required. 

The  longer  the  focal  length  of  the  objective  the  more  accurate 
the  filter  must  be  for  copying.  This  is  why  the  50mm  lens  is  excel- 
lent because  of  its  short  focal  length. 

Collapsible  Reproduction  Stand 

While  traveling  or  when  working  in  libraries  or  similar  places  the 
complete  equipment  must  be  kept  as  light  and  portable  as  possible.  For 
this  use,  the  Collapsible  Reproduction  Stand  is  available.  This  apparatus 
consists  of  a  number  of  tubes  fitting  into  one  another,  two  supporting  base 
bars,  and  the  extension  arm  for  attaching  the  Leica  or  the  Sliding  Copy 
Attachment.  As  the  upright  is  about  22  inches  high  the  No.  2  and  No.  3 
supplementary  front  lenses  can  be  used.  The  vertical  and  horizontal  tubes 
have  graduated  scales  in  fractions  of  an  inch. 

When  the  Leica  is  used  with  the  Front  Lenses  a  plumb  weight  is  used 
for  determining  the  exact  center  of  the  object  to  be  copied.  Then  by  refer- 
ring to  the  lens  table  booklet,  which  is  supplied  with  the  lenses,  the  exact 
focus  and  distance  settings  can  be  quickly  made.  A  special  light  bracket 
containing  two  lights  is  also  available  for  attaching  to  the  extension  arm  of 
this  outfit. 

Fig.  137  Reproduction 
Stand  Equipped  with  Slid- 
ing Arm,  Illuminator, 
Leica  with  Wintu  Angle 
View  Finder,  Measuring 
Tape,  and  Wire  Cable  Re- 
lease. -  The  Collapsible 
Stand  is  Smaller  but  a 
Similar  Set-up  can  be 


Auxiliary  Reproduction  Devices 

For  certain  types  of  close-up  photography  the  Auxiliary  Eeproduction 
Attachments  are  of  value.  These  attachments  provide  a  fixed  focusing  ar- 
rangement which  can  be  applied  for  special  areas  from  1x1%  inches  up  to 
8%  x  12%  inches.  The  Belun  Device  is  used  with  the  Leica  equipped  with 
the  Elmar  50mm  lens  for  obtaining  1:1  or  natural  size  copies.  This  same 
equipment  is  also  available  for  the  Hektor  and  Summar  50mm  lenses,  and 
the  Elmar  35mm  lens.  This  equal-size  reproduction  device  may  be  used  for 
copying  portions  of  maps,  coins,  postage  stamps,  finger  prints,  handwriting 
specimens,  small  insects,  plants,  seeds,  and  any  other  object  which  can  be 
included  in  the  1x1%  inch  area.  The  accompanying  illustration  will  show 
how  this  attachment  is  set  up. 

The  Behoo  Device  is  used  for  obtaining  reduction  ratios  of  1:1%,  1:2 
and  1:3  with  the  Leica.  The  greatest  sizes  of  the  objects  at  the  three 
different  ratios  are,  36  x  54mm,  48  x  72mm,  and  72  x  108mm.  As  a  com- 
plete direction  booklet  is  available  for  this  attachment  as  well  as  the  other 
Auxiliary  D  Copy  Devices  it  will  not  be  necessary  to  make  a  reprint.  The 
Behoo  Device  uses  three  Extension  Tubes  for  securing  the  three  different 
fixed  focusing  positions.  When  the  No.  2  and  No.  3  Front  Lenses  are  used 
there  is  an  attachment  known  as  the  Beooy  which  covers  areas  from 
3%  x  5  inches  up  to  8%  x  12%  inches.  Still  another  similar  attachment  is 
known  as  the  Bazoo  which  is  a  combination  of  the  Behoo  and  the  Beooy 
Devices.  The  accompanying  illustrations  will  give  a  good  idea  about  the 
way  in  which  these  copy  attachments  are  set  up. 

Fig.  138  The  Belun  1:1  Copy  De- 
vice used  for  Making  Actual  size 
Copies  1x1%  inches. 

Fig.  139  Auxiliary  Eeproduction 
Device  for  use  with  Extension 
Tubes  and  Front  Lenses  directly  on 



Special  Rotating  Copy  Attachment 

Still  another  type  of  copy  attachment  which  has  recently  been  made 
available  is  the  Rotating  Copy  Attachment  which  serves  the  same  purpose 
as  the  Sliding  Focusing  Copy  Attachment  already  described.  The  Rotating 
Device,  as  shown  in  the  illustrations,  can  be  used  for  copying-  all  areas 
similar  to  the  Sliding-  Attachment.  The  booklet  accompanying  this  Rotating 
Copy  Device  gives  complete  tables  and  directions  for  operation. 

Fig.  140  Rotating  Stage  Copy  De- 
vice. Note  5x  Magnifier  on  Device 
and  30x  Magnifier  at  Lower  Left. 

Fig.  141  Rotating  Stage  Copy 
Device  as  used  in  vertical  po- 

A  very  convenient  attachment  for  the  Rotating  Copy  Attach- 
ment is  known  as  the  Rotating  Stage  Plate  which  can  be  used  for 
photographing  small  objects  such  as  minerals,  medical  specimens,  art 
objects,  photographs,  or  handwriting.  This  attachment  (Fig.  140) 
has  a  magnification  range  from  1:1  to  1:4  and  focusing  may  be 
secured  by  direct  visual  inspection  of  the  ground  glass  or  by  using 
the  calibrated  upright.  It  will  be  noted  that  there  are  three  engraved 
lines  at  the  four  different  focusing  positions  on  the  upright.  The  top 
line  in  each  ease  is  for  use  with  the  Summar  50mm  lens,  the  second 
line  for  the  Elmar  50mm  lens,  and  the  bottom  line  for  the  Hektor 
50mm  lens.  At  the  1:1  position  the  picture  area  is  the  same  size  as 
the  Leiea  negative  or  approximately  1  x  1%  inches  while  at  the  1  -A 
point  the  maximum  area  covered  is  3  4/5  x  5  3/5  inches.  "When  using 


the  calibrate  scale  of  the  Kotating  Stage  Plate  It  is  necessary  to  use 
the  intermediate  rings  recommended  for  this  arrangement.  Here 
again  it  is  possible  to  obtain  from  the  Leitz  Company  a  complete 
direction  booklet  and  also  a  special  chart  giving  the  exact  areas  cov- 
ered with  full  information  about  intermediate  tubes  and  the  distances. 

Fig.  142  Special  Copy  Device  with 
bellows  extension.  Note  King  Illu- 
minating Device  used  for  Securing 
Proper  Illumination  of  Specimens. 

When  using  the  Special  Eotating  Copy  Attachment  it  is  possible 
to  photograph  objects  17  x  26  inches  in  size  or  minute  objects  only 
1/10  x  3/20  inches  in  size.  When  a  microscope  is  added  as  shown 
in  Figure  143  one  can  obtain  magnifications  up  to  several  thousand 
diameters.  A  brief  summary  of  the  basic  equipment  for  the  Special 
Rotating  Attachment  as  shown  in  Figures  142  and  143  is  listed  as 
follows : 

1.  A  19  x  27  inch  baseboard  mounted  on  shock  absorbing  springs  which 
can  be  clamped  rigidly  or  left  in  free  suspension. 

2.  An  upper  and  lower  copying  arm  which  can  be  moved  as  required  for 

3.  The  upper  aim  is  fitted  with  a  clamping  screw  for  holding  the  Eotating 
Copy  Attachment  while  the  lower  arm  holds  the  lens  mount  and  the 
extension  bellows. 

4.  A  fine  focusing  ring  is  provided  at  the  base  of  the  lower  arm. 

5.  The  upright  pillar  is  4  feet  high,  and  1%  inches  thick. 

6.  A  ring  illuminator  with  rheostat  provides   the  maximum   of  lighting 

7.  The  5X  and  SOX  magnifiers  are  used  with  this  equipment  in  the  same 
way  as  required  for  the  Sliding  Copy  Attachment. 



Fig.  143  Sliding  Copy  Device  equipped  for  use  with  the  Model  FF  250- 
exposure  Leica.  Illustration  shows  camera  in  position  for  use  with  the 

250  Exposure  Leica  Model  FF 

When  many  photographs  are  to  be  made  of  book  pages  or  other  sub- 
jects the  250  exposure  Leica  is  valuable  as  a  time  saver.  This  camera  can 
be  used  on  the  regular  Sliding  Arm,  on  a  tilting  top  tripod,  or  in  connection 
with  a  special  Sliding  Copy  Attachment.  This  camera  can  also  be  used 
conveniently  with  the  microscope  for  making  many  photographs  in  rapid 
succession  of  still  or  moving  objects. 


As  the  subject  of  copying  is  such  a  broad  one  an  entire  book 
could  easily  be  written  in  order  to  include  the  many  interesting 
methods  and  applications.  However  this  chapter  will  give  the  essen- 
tials from  which  the  Leica  user  can  select  the  information  required 
for  his  own  work. 


The  Fliers 

A  Four-Negative  Photo-Montage 

John  T.  Moss,  Jr. 




Undoubtedly  the  best  way  in  which  to  view  Leica  pictures  is 
by  projection  upon  a  screen.  In  this  way  the  projected  image  not 
only  has  a  large  area,  but  it  also  yields  more  of  a  plastic  quality 
which  closely  resembles  the  original  subject.  Such  pictures  may 
be  projected  in  full  natural  colors,  in  various  tones,  as  well  as  the 
ordinary  black  and  white  film  or  glass  slides.  In  these  projected 
pictures,  a  large  group  of  people  may  be  able  to  enjoy  the  same 
picture  at  the  same  time.  As  most  Leica  pictures  are  made  with 
shorter  focal  length  lenses,  the  negatives  produce  positives  which 
give  an  almost  stereoscopic  effect.  This  is  due  to  the  excellent  depth 
of  focus  in  the  Leica  lens.  In  contrast  to  the  projected  positive,  tlie 
small  5  x  7  or  8  x  10  inch  paper  prints  do  not  create  the  luminosity 
and  brilliance  which  are  to  be  found  in  the  projected  picture. 

One  reason  why  a  greater  use  and  appreciation  of  the  projected 
image  is  not  found  is  possibly  because  such  pictures  do  not  convey 
the  full  interpretation  of  the  original  negative.  This  may  be  due  to 
the  following : 

1.  The  positive  film  or  glass  slide  may  lack  contrast  and  brilliance. 

2.  The  picture  may  not  be  composed  properly  on  the  slide  or  the 
original  negative  may  not  have  a  pleasing  composition. 

3.  The  positive  may  be  overexposed  and  thus  be  too   dark  on  the 
projected  screen,  or  it  may  possibly  be  underprinted  with  the  resulting*  loss 
of  detail  and  depth. 

4.  The  projected  picture  may  have  pin  holes,  dust  spots,  finger  prints 
or  other  blemishes. 

5.  The  center  of  interest  may  be  lost  in  a  maze  of  useless  detail. 

6.  Possibly  the  positive  may  lack  sharpness  due  to  improper  focusing 
or  uneven  pressure  in  the  case  of  contact  printing. 

In  many  cases,  an  interesting  Leica  negative  might  be  made  into  a 
slide  for  projection  instead  of  viewing  the  same  picture  on  an  8  x  10  inch 
enlargement.  The  projected  picture  presents  a  larger  and  more  dramatic 
effect.  At  the  same  time,  the  film  or  glass  positive  emulsion  has  a  greater 
latitude  in  the  shadows  and  highlights  of  the  image  itself,  as  compared 
to  the  paper  enlargement.  This  is  due  to  the  fact  that  there  is  a  light 
illuminating  the  entire  picture.  In  the  projected  image,  even  the  blackest 
shadows  have  illuminated  details,  providing  the  positives  have  been  prop- 


erly   made,   while   in   the   paper   print   there    cannot   be   such  transmircecl 


What  Makes  Good  Positives 

Leiea  negatives  can  be  prepared  from  many  different  subjects 
wiiicli  later  may  be  made  up  into  film  and  glass  slide  sets.  For 
example,  these  sets  of  positives  may  include  pictures  selected  from 
your  vacation,  travels,  photographs  of  children  and  pets,  or,  you  may 
have  sets  illustrating  your  particular  hobby  by  photographing:  the 
American  scene,  geological  formations,  architectural  subjects,  car- 
toons, wild  flowers,  trees,  insects  and  many  other  subjects  which 
lend  themselves  readily  to  photographic  interpretation.  After  illus- 
trating such  subjects,  it  is  possible  to  use  these  pictures  for  lecture 
and  visual  education  purposes,  or  for  your  own  persona]  entertain- 
ment. In  the  case  of  film  slides,  these  pictures  may  be  printed  in 
groups  of  twenty  to  forty  on  one  strip  of  film.  On  the  other  hand, 
the  2  x  2  inch  glass  slides  may  be  made  individually  and  added  to  the 
sets  at  any  time.  There  is  something  to  be  said  for  each  method. 
The  film  slides  are  made  more  inexpensively  while  the  glass  slides  are 
more  permanent  and  may  be  re-arranged  during  projection.  In 
addition  to  using  the  film  and  glass  slides  for  general  purposes,  they 
are  valuable  in  the  commercial  field  for  use  in  demonstrating  sales 
methods,  new  products,  as  well  as  in  training  workers  and  salesmen. 

The  new  Leica  Duf  ay  color  film  is  excellent  for  commercial, 
educational,  and  for  general  subjects  as  well.  This  colorfilm  pro- 
duces a  very  satisfactory  result  when  projected. 

One  of  the  most  important  advantages  of  making  Leica  pictures 
for  projection  is  that  these  pictures  require  small  storage  space. 
For  example,  twenty-five  rolls  of  positive  film  slides  may  easily  be 
carried  in  a  small  container.  These  film  rolls  may  include  over  1,000 
pictures.  With  positive  film  costing  only  two  or -three  cents  per  foot, 
the  film  of  1,000  pictures  would  entail  a  cost  of  about  $3.00,  while 
1,000  8  x  10  inch  enlargements  will  probably  come  to  over  $60.00.  A 
remarkable  difference !  Even  the  2x2  inch  glass  slides  are  quite 
small  and  light  in  weight  when  compared  to  the  standard  3*4  x  4 
inch  glass  slides  which  are  commonly  used  in  the  large  projectors. 

A  thorough  understanding  of  this  chapter  on  the  making  of 
Leica  positives,  along  with  the  contents  of  the  chapter  on  Visual 
Education  is  essential  The  two  are  closely  related.  In  the  same 
way,  all  the  other  chapters  in  this  book  are  likewise  allied,  directly 
or  indirectly,  to  the  making  of  film  positives.  The  making  of  the 
original  Leica  negative  is  just  as  important  as  the  fine  technique  in 


Making  Positives 

the  making  of  the  final  film  or  glass  slide  positive  for  projection. 
In  other  words,  a  poor  Leica  negative  will  not  produce  a  superb 
Leiea  positive.  On  the  other  hand,  an  excellent  Leiea  negative  can 
very  easily  be  made  into  a  very  poor  positive  unless  proper  steps 
in  its  preparation  are  carefully  observed. 

The  Two  Positive  Printing  Processes 

There  are  two  ways  in  which  to  make  the  Leica  positive  film  or 
glass  slide.  The  most  common  method  is  by  actual  contact  printing 
which  is  accomplished  by  placing  the  Leica  negative  directly  in  con- 
tact with  the  unexposed  positive  film  or  glass  plate.  The  other  method 
is  by  placing  the  negative  into  one  of  the  Leica  enlargers  and  then 
printing  directly  by  projection.  Here  again,  there  are  advantages  in 
both  methods,  the  former  possibly  being  completed  a  little  more  rapidly 
and  at  the  same  time  requiring  only  a  minimum  amount  of  equipment, 
while  in  the  case  of  projection,  it  is  easier  to  omit  portions  of  the  image 
in  case  a  negative  must  be  balanced  correctly  in  printing.  The  pro- 
jection method  helps  in  eliminating  dust  particles  and  also  the  best 
portions  of  the  negatives  may  be  utilized.  Both  of  these  methods  will 
be  described  in  detail  later  in  the  chapter. 

Contact  Positive  Printers 

The  Eldia  Film  Printer  represents  one  of  the  simplest  arrangements 
for  the  contact  printing  of  Leica  negatives  either  upon  paper  or  positive 
35mm  film  strips.  This  printer  will  hold  approximately  eight  feet  of  posi- 
tive film.  The  raw  stock  is  wound  upon  one  spool  and  unwound  upon  an- 
other take-up  spool  after  each  contact  print  has  been  made.  A  ratchet 
clicks  for  each  space  of  three-quarters  of  an  inch  which  represents  the 
single  frame  picture  area.  Two  clicks  of  the  ratchet  represent  the  length 
of  the  Leica  picture.  The  Eldia  Printer  is  supplied  with  the  standard 
frame  size  for  the  Leica  negative.  However,  in  case  single  frame  nega- 
tives are  to  be  printed,  it  is  possible  to  secure  a  single  frame  window 
which  is  interchangeable  on  the  Eldia  Printer.  The  accompanying  illustra- 
tions will  give  a  more  definite  idea  about  the  appearance  of  the  printer. 

Fig.  146     Eldia   Printer.     For  Making   Contact   Prints   on   Positive   Film 
or   Paper 


When  using  the  Eldia  Printer,  it  is  possible  to  print  each  negative  in 
its  original  sequence,  or  if  necessary,  important  negatives  only  may  be 
selected  and  printed  upon  the  positive  film  stock,  which  is  later  developed 
and  used  in  one  of  the  projectors.  In  doing  this,  the  negative  is  pulled 
past  the  window  of  the  printer  until  the  proper  negative  appears.  The  lid 
is  then  clamped  into  position  and  the  exposure  made.  Do  not  wind  the 
film  when  the  top  lid  is  closed  or  the  film  will  become  scratched. 

_fU  r 

,      1  ,  „ 



-••  °  °  p  —  "•  u 


)  0  0 








.   _  '   —  j  'S  

Fig.  147  Positive  Film  or  Paper  Passes  over  Ratchet  Wheel  and  under 
Take-up  Spool  at  Eight.  Negative  Film  Passes  Through  Channel  of 
Hinged  Cover. 

Fig.  148    Alternate  Method:   Paper  and   Negative   are  Both   Passed  over 
the  Ratchet  and  over  the  Take-Up  Spool  at  the  Right. 

Directions  for  Operating  the  Eldia  Printer 

Use  standard  safety  base  or  non-inflammable  positive  film  stock. 
This  may  be  purchased  in  various  lengths  from  any  photographic 


Making  Positives 

1.  When  preparing  to  load  the  Eldia  Printer,  cut  off  about  five  or 
six  feet  of  positive  film  and  wind  this  upon  the  spool  in  the  Eldia  Printer 
opposite  to  the  winding  spool  which  has  a  slightly  longer  knob  for  turning. 

2.  The  winding  or  take-up  spool  is  placed  in  the  chamber  next  to  the 
small   ratchet  wheel   which   marks   the    successive   advance    of   the   Leica 
frames  during:  printing.     After  the  unexposed  film  has  been  wound  upon 
the  supply  spool,  the  free  end  is  pointed  and  attached  to  the  take-up  spool. 
Naturally,  the  film  has  been  wound  with  the  emulsion  side  out.     The  two 
spools  are  ^  now  placed  in  their  respective  chambers  in  the  Eldia  Printer, 
as  shown  in  the  accompanying  line  drawing1. 

3.  Insert  the  Leica  negative  into  the  grooves  which  are  to  be  found 
on  each  side  of  the  glass  plate  in  the  cover  of  this  printer,  the  emulsion 
side  of  the  negative  facing  out.     In  other  words,  the  emulsion  side  of  the 
unexposed  positive  and  the  emulsion  side  of  the  Leica  negative  must  come 
face  to  face  in  actual  contact  when  the  cover  of  the  printer  is  closed. 

4.  After  the  printer  has  been  closed,  it  is  possible  to  judge  the  density 
of  the  negative  by  holding  the  printer  over  a  small  light  box,  or  in  case 
such  a  box  is  not  available,  hold  the  printer  up  in  front  of  a  low  power 

'  light  bulb  for  a  few  seconds  in  order  to  estimate  the  density  of  the  negative 
through  the  red  plate  which  is  to  be  found  at  the  base  of  the  printer. 

5.  One  of  the  easiest  methods  of  exposing  each  successive  negative 
when  using  this  printer  is  by  placing  the  apparatus  under  the  Leica  en- 
larger.     In  case  the  light  in  the  Leica  enlarger  is  too  strong,  one  or  two 
pieces  of  tissue  paper  may  be  placed  in  the  position  which  would  ordi- 
narily be  occupied  by  a  negative  for  enlarging.    This  method  provides  bet- 
ter diffusion  of  the  light.     The  projection  lens  in  the  enlarger  should  be 
thrown  out  of  focus. 

6.  After  one  exposure  has  been  made,  unhook  the  cover  of  the  Eldia 
Printer  and  pull  the  Leica  negative  to  the  next  picture.    At  the  same  time, 
turn  the  positive  film  until  two  clicks  are  heard  in  the  case  of  Leica  films. 

7.  Make  the  exposure,  after  the  density  of  the  negative  has  been  de- 
termined by  flashing  on  the  small  light  under  the  printer.     Proceed  with 
this  method  until  all  the  pictures  have  been  printed. 

8.  Make  certain  that  the  vertical  and  horizontal  negatives  are  printed 
in  the  same  way.    In  other  words,  do  not  reverse  the  negatives  so  that  the 
vertical  or  horizontal  pictures  show  on  the  screen  in  different  directions 
when  projecting.    Also,  remember  that  if  the  first  picture  is  to  start  at  the 
beginning  of  the  positive  film,  the  print  should  be  made  in  such  a  way  as 
to  show  it  at  the  beginning  of  the  roll  and  not  reversed,  which  may  be  the 
case  if  care  is  not  utilized.     Simply  remember  that  the  positive  picture 
is  placed  into  the  projector  upside-down  with  the  emulsion  side  facing  the 
projection  lamp. 

9.  Before  printing  the  full  roll  of  Leica  positives,  it  is  best  to  make 
a  few  test  exposures  of  various  negatives  with  varying  densities.     To  do 
this,  cut  up  short  two  inch  lengths  of  positive  film  and  place  directly  into 
the  printer  so  that  the  emulsion  side  will  come  into  contact  with  the  emul- 
sion side  of  the  negative  when  the  cover  of  the  printer  is  slipped  shut. 
Develop  each  test  film  in  exactly  the  same  way  the  full  length  of  positive 
film  is  to  be   developed.     Three   or  four   single   exposure   strips  may  be 
easily  developed  in  a  small  tray  for  the  full  time  required  for  the  devel- 
oper.   After  the  test  films  have  been  cleared  in  the  hypo,  rinse  for  half 
a  minute  in  water  and  then  examine  them  by  actual  projection  in  the  en- 
larger  or,  better  yet,  use  one  of  the  Leica  projectors.     The  wet  emulsion 


will  very  quickly  melt  if  exposed  too  long  to  the  heat  of  the  projector. 
Until  you  become  an  expert  in  judging  the  test  exposures,  it  is  always 
best  to  examine  these  test  films  by  projection. 

10.  Make  certain  that  the  glass  plate  in  the  Eldia  Printer  is  thor- 
oughly cleaned  and  also  keep  the  negative  and  positive  film  free  from 
dust  particles  which  may  show  on  the  finished  positive  film.    Do  not  make 
more  than  36  pictures  on  one  length  of  film,  if  it  is  to  be  developed  in  a 
Reelo  or  Correx  Tank. 

11.  After  the  completed  strip  of  positive  film  has  been  exposed,  de- 
velopment is  carried  out  in  the  Correx  or  Reelo  Tanks  in  a  manner  similar 
to  that  in  which  the  Leica  negative  was  developed.    The  only  exception  in 
the  process  is  that  the  film  is  developed  in  a  special  developer  which  ordi- 
narily takes  about  five  minutes  for  complete  development. 

12.  The  Glass  Developing  Drum  can  also  be  used  for  developing  the 
positive   films.     This    drum    is   quite   essential   for   developing   the    Leica 
Dufaycolor  film  also. 

All  positive  films  made  for  projection  purposes  should  be  thoroughly 
hardened  after  development.  One  of  the  simplest  hardeners  is  Chrome 
Alum  described  in  the  Developing  Chapter.  After  the  film  has  been  hard- 
ened, cleared  in  the  acid  fixing  solution,  washed,  and  then  dried,  it  should 
be  rolled  up  with  the  emulsion  side  out  if  it  is  to  be  used  in  the  Umino 
or  Umena  projectors.  If  one  of  the  Udimo  projectors  are  to  be  used  the 
film  may  be  wound  with  the  emulsion  side  in. 

Making  the  Leica  Glass  Positive 

Glass  2x2  inch  positives  may  be  made  in  the  Eldur  Glass  Slide 
Printer  very  quickly  by  contact  printing,  as  follows : 

1.  The  method  of  inserting  the  Leica  negative  is  shown  in  the  ac- 
companying illustration.     The  2  x  2  inch  glass  plate  is  placed  with  the 
emulsion   side   down   directly   over   the   Leica  negative.     The   top   hinged 
pressure  plate  is  then  clamped  down  to  hold  the  glass  plate  in  contact  dur- 
ing exposure. 

2.  The  Eldur  Printer  is  then  placed  under  the  enlarger  and  the  ex- 
posure made  by  turning  on  the  enlarger  light  for  the  correct  exposure 
time,  which  may  vary  from  2  to  10  seconds,  depending  on  the  negative  and 
the  stop  used  in  the  enlarger  lens.     Always  use  the   same  illumination 
when  making  positives  in  order  to  help  in  making  the  exposure  estimate 
more  uniform.     A  test  slide  should  be  made  first  by  turning  on  the  en- 
larger  light  and  then  make  four  exposures  of  2,  4,  6,  and  8  seconds  each 
on  the  same  plate,  by  moving  a  card  across  at  each  step.    When  developed, 
the  test  slide  may  be  projected  and  the  best  exposure  quickly  determined 
for  the  next  slide.    Sometimes  it  is  more  convenient  and  also  less  expen- 
sive to  use  a  Bromide  paper  which  has  the  same  speed  as  the  plate  for 

3.  The  glass  slides  are  developed  in  the  usual  slide  developer  which 
is  given  in  the  same  package  in  which  the  2x2  inch  glass  slides  come. 

The  Gevaert  Company  supplies  the  2x2  inch  glass  slides  in  a  medium 
as  well  as  contrast  grade.  Barnet  slides  may  also  be  secured  in  the  2x2 
inch  size.  When  making  glass  slides,  it  is  best  to  have  both  contrasts  avail- 
able, in  order  to  obtain  the  best  results  from  negatives  which  may  be  con- 
trasty  or  flat.  Usually,  the  contrast  grade  will  be  used.  After  exposing, 
developing  and  fixing  the  glass  slide,  it  should  be  tested  in  the  projector 


Making  Positives 

Fig.  149  Special  Eldur  Contact 
Printer  for  Making  2x2  inch 
(50mm  x  50mm)  Glass  Slides 

for  correct  exposure  and  development.  While  still  wet,  it  may  safely  be 
projected  two  or  three  seconds.  After  making-  thousands  of  glass  slides, 
I  still  recommend  that  each  slide  be  placed  in  the  projector  and  flashed 
upon  the  screen  for  an  instant  since  this  is  the  only  way  in  which  the  finest 
glass  slides  can  be  produced.  If  the  light  of  the  projector  is  flashed  for 
only  two  or  three  seconds  through  the  wet  slide,  there  will  be  no  effect 
upon  the  positive.  However,  if  the  wet  plate  is  allowed  to  remain  in  the 
projector  for  a  half  minute  or  more,  the  emulsion  will  warm  up  and  melt, 
thus  ruining  the  slide.  It  is  very  easy  to  have  the  projector^  in  the  dark- 
room for  this  purpose.  A  small  image  projected  upon  a  white  cardboard 
is  sufficient  for  determining  the  quality  of  the  slide. 

A  good  developer  for  use  with  the  2x2  inch  glass  slides  is  prepared 
as  follows: 

Gevaert  Contrast  Developer  for  Slides 

Metol     11  grains  0.75  grams 

Hydroquinone    45       "  3.0       " 

Sod.  Sulphite  (des.)    175       "  25.0       " 

Sod.  Carbonate  (monohydrate)  350       "  53.0       " 

Pot.   Bromide 8       "  0.5       " 

Water  to  make 16  oz.  500.0  cc 

The  chemicals  must  be  dissolved  in  the  order  named.  A  very  good 
plan  is  to  dissolve  every  product  in  water,  mixing  in  the  order  named.  The 
bath  is  then  filled  up  with  water  to  the  mentioned  quantity. 

At  a  temperature  of  65°  P.,  lantern  plates  develop  in  from  1%  to 
2%  minutes. 

Make  certain  that  the  exposure  is  such  that  the  positive  plate  will 
remain  in  the  developer  for  at  least  two  and  a  half  to  three  minutes 
without  becoming  overdeveloped.  In  case  the  image  flashes  up  too 
soon  and  the  plate  is  removed  at  the  same  time  from  the  developer,  the 
resulting  positive  will  not  have  the  rich  transparency  and  brilliance 
which  occurs  when  the  plate  is  properly  exposed  and  fully  developed. 
This  is  where  many  workers  make  a  mistake.  Never  underdevelop 


a  positive  but  on  the  contrary,  carry  the  development  to  the  recom- 
mended length  of  time.  Even  a  minute  over  this  time  will  be  better 
than  a  minute  under,  The  Universal  Developer  described  in  the  chap- 
ter on  Enlarging  Papers  may  also  be  used  for  positive  films  or  glass 

"Whenever  more  contrasting  results  are  required  on  positive  glass 
plates,  it  is  necessary  to  use  a  contrast  developer.  The  Eastman  D-ll 
Developer  produces  good  contrast,  while  the  Eastman  D-9  Caustic 
Developer  produces  extreme  contrast.  The  D-9  Developer  is  par- 
ticularly well  suited  for  line  work,  where  extreme  contrast  is  desired. 

Hydroquinone- Caustic  D-9  Developer 

For  Process  and  Panchromatic  Process  Films  and  Glass  Slides 
For  Tray  Development 

Stock  Solution  A 

Avoirdupois  Metric 

Water  (about  120°  F.)  (52°  C.) 16       ounces  500.0  ec. 

Sodium    Bisulphite    %  ounce  22.5  grams 

Hydroquinone     %  ounce  22.5  grams 

Potassium    Bromide    %   ounce  22.5  grams 

Cold  water  to  make 32       ounces  1.0  liter 

Sirock  Solution  B 

Cold  water    32       ounces  1.0  liter 

Sodium  Hydroxide   (Caustic  Soda) 1%  ounces  52.5  grams 

Dissolve  chemicals  in  order  given. 

Use  equal  parts  of  A  and  B  and  develop  for  not  more  than  two  min- 
utes at  65°  F.  (18°  C.). 

Cold  water  should  always  be  used  when  dissolving  sodium  hydroxide 
(caustic  soda)  as  considerable  heat  is  evolved.  If  hot  water  is  used,  the 
solution  will  spatter  with  violence  and  may  cause  serious  burns  if  the 
alkali  spatters  on  the  hands  or  face.  Solution  A  should  be  stirred  thor- 
oughly when  the  caustic  alkali  is  added;  otherwise  the  heavy  caustic  solu- 
tion will  sink  to  the  bottom. 

Wash  thoroughly  after  development  and  before  fixing  to  prevent 
stains  and  dichroic  fog. 

When  using  the  D-9  Caustic  Developer,  mix  a  small  amount  in  a 
small  tray  or  dish  which  is  only  a  little  larger  than  the  2x2  inch  glass 
plate.  Use  developer  only  sufficient  to  cover  the  plate.  Upon  mixing  the 
two  solutions,  the  developer  oxidizes  quite  rapidly  and  after  eight  or  ten 
minutes,  at  the  most,  the  developer  should  be  discarded.  In  the  meantime, 
the  slides  may  be  developed.  As  this  is  a  strong  and  rapidly  working 
developer,  make  certain  that  the  positive  plates  are  not  overexposed, 
since  fine  details  in  a  line  drawing  or  a  printed  page  will  not  show  dis- 
tinctly unless  correct  exposure  has  been  made.  However,  with  the  correct 
exposure  and  the  caustic  developer,  a  brilliant  contrast  negative  will  result. 

Using  Projection  Paper  for  Testing 

When  making  film  or  glass  slides,  it  is  possible  to  use  a  bromide 
projection  paper  cut  into  small  sizes  and  used  in  place  of  the  film  or 


Making  Positives 

Fig.  150      Saloon  of  the  Gold-Rush  Days          Willard  D.  Morgan 

Fig.  151      Country  Club  of  Gold-Rushers 

Willard  D.  Morgan 

glass  plate  for  testing  the  exposures,  A  paper,  such  as  the  Agfa 
Brovira  medium,  or  contrast  has  a  printing  time  very  similar  to  posi- 
tive film  or  glass  plate  emulsions.  With  a  little  experience,  the  proper 
ratio  between  the  paper  and  the  positive  emulsions  may  be  easily  de- 
termined for  this  paper,  as  well  as  any  other  make  of  Bromide  papers. 
Such  a  method  of  making  tests  is  economical  because  a  full  glass  plate 
does  not  have  to  be  exposed  in  order  to  find  out  the  correct  exposure 
time.  At  the  same  time  these  contact  paper  prints  may  be  used  for 
indexing  purposes  or  for  cross  references  after  the  slides  have  been 
made.  It  is  a  good  plan,  in  fact,  to  make  a  paper  contact  print  of 
every  negative  which  is  made  into  a  positive  for  projection.  These 
paper  prints  are  useful  for  classifying  the  pictures  later.  There  is 
a  special  metal  pressure  plate  which  may  be  placed  over  the  square 
rubber  plate  which  is  used  in  the  Eldur  Printer.  This  metal  pressure 
plate  permits  the  making  of  paper  contact  prints  in  the  Eldur  Printer. 
It  is  quickly  removed  when  glass  plates  are  to  be  made. 

After  each  positive  glass  plate  has  been  developed,  it  should  be 
rinsed  for  a  few  seconds  in  fresh  water  and  then  placed  in  the  hypo 
clearing  solution  for  about  eight  to  ten  minutes.  After  clearing,  the 
slide  is  then  placed  in  running  water  and  washed  for  one-half  hour. 
When  washing  has  been  completed,  wet  a  piece  of  cotton  or  nse  a  wet 
viscose  sponge  for  swabbing  off  both  sides  of  the  plate  which  is  then 
placed  in  a  drying  rack  in  a  location  free  from  dust.  A  close-meshed 
linen  cloth  may  be  laid  over  the  drying  rack  in  order  to  keep  out  dust 
particles  which  may  settle  on  the  wet  emulsion  of  the  plate  and  later 
show  up  on  the  projection  screen. 

When  all  the  slides  are  dry,  they  should  be  projected  before  bind- 
ing in  order  to  cheek  on  the  quality.  In  case  there  are  scratches,  pin 
holes  or  other  defects,  the  slide  must  either  be  touched  up  or  discarded. 
Small  pin  holes  and  breaks  in  the  emulsion  can  usually  be  eliminated 
by  spotting  with  a  fine  brush  and  black  spotting  ink.  The  Chinese 
Ink  stick,  which  may  be  purchased  at  most  photographic  dealers,  is 
very  handy  for  this  purpose.  Some  slides  may  require  opaquing 
around  the  principal  object.  This  is  easily  done  by  painting  with  a 
good  opaque  solution  which  dries  quickly.  Slides  showing  machinery 
parts,  and  copies  of  irregular  subjects  which  are  to  be  shown  without 
a  background,  will  require  this  method  of  opaquing  before  binding. 

Mounting  the  Finished  Glass  Slide 

After  the  glass  slide  is  dry,  secure  a  clear  cover  plate  together  with 
a  cut  out  mask  and  a  package  of  lantern  slide  binding  tape.  The  binding 
tape  can  be  cut  into  four  lengths  of  two  inches  each,  or  if  preferred,  one 
full  length  about  eight  and  one-half  inches  long  may  be  cut.  Place  the 


Making  Positives 

cut  out  paper  mask  over  the  emulsion  side  of  the  positive  in  such  a  way 
that  the  clear  portions  of  the  positive  surrounding  the  picture  are  covered. 
Next,  place  the  clear  cover  glass,  which  has  previously  been  washed  and 
polished  dry,  over  the  mat  and  the  positive  plate.  Hold  both  plates  to- 
gether and  paste  the  paper  binding  tape  around  the  edges.  Make  sure 
that  the  emulsion  side  of  the  positive  plate  is  always  covered  by  the  glass 
plate.  If  the  emulsion  side  is  on  the  outside,  it  will  quickly  be  damaged. 

Film  positives  may  be  cut  with  scissors  and  bound  between  glass 
plates  if  desired.  Some  Leica  users  prefer  this  method  since  the  pictures 
may  be  made  at  smaller  expense.  Two  or  three  positives  may  be  made 
of  the  same  negative  in  case  there  is  any  doubt  about  the  exposure.  The 
best  positive  is  then  selected  for  binding  between  the  two  clear  glass 
plates  with  the  paper  mask  between.  The  film  positive  should  be  attached 
to  the  paper  mask  by  one  or  two  small  pieces  of  the  paper  binding:  tape 
in  order  to  keep  the  picture  centered  while  "binding.  This  method  is  espe- 
cially recommended  for  the  natural  color  films,  such  as  the  Agfacolor, 
Dufaycolor  and  Lumiere. 

After  the  glass  slide  is  bound,  it  should  be  spotted  by  placing  a 
small  white  square  of  gummed  paper  or  photo  cloth  in  the  upper  right 
corner  of  the  slide  when  it  is  in  its  correct  position  for  projecting.  In 
other  words,  hold  the  slide  before  you  so  that  it  looks  correct.  That  is, 
the  slide  should  appear  in  the  same  orientation  as  the  original  subject. 
Then,  turn  the  slide  so  that  the  subject  is  up-side-down  with  the  emulsion 
side  facing  toward  you.  Place  white  spot  on  the  tipper  right  corner  of  the 
slide.  When  the  slides  are  being  projected,  it  is  very  easy  to  place  them 
in  the  projector  in  their  proper  position  without  difficulty,  simply  by  watch- 
ing the  reference  spot. 

Ail  glass  slides  spoiled  by  wrong  exposure,  developing,  or  any  other 
cause,  should  be  saved  and  used  for  cover  glasses  later.  These  discarded 
slides  may  be  soaked  in  hot  water  and  strong  soap  in  order  to  soften  and 
remove  the  emulsion.  A  razor  blade  is  good  for  scraping  off  the  emulsion. 
Give  the  glasses  a  final  wash  in  another  soap  and  water  bath  and  then 
wipe  thoroughly  dry  with  a  clean  linen  cloth.  The  glasses  are  now  ready 
for  use  in  binding  the  good  lantern  slides. 

Still  another  method  of  preparing  film  positives  for  projection  is 
by  mounting  three  positive  films  between  two  clear  glass  plates  which 
measure  35  x  120mm.  These  plates  are  matted  and  bound,  similar  to  the 
2x2  inch  glass  plates.  The  Udimo  Projectors  have  a  special  slide  holder 
for  accommodating  this  longer  sized  plate.  In  the  case  of  stereo  positives, 
this  method  of  binding  is  excellent  as  the  Stereo  Viewer  accommodates 
the  35  x  120mm  slide. 

Making  Film  or  Glass  Slides  by  Projection 

My  favorite  method  of  making  film  or  glass  slides  is  by  using  one 
of  the  Leica  enlargers.  The  negative  is  placed  in  the  enlarger  with  the 
emulsion  side  facing  down  as  usual,  while  the  unexposed  film  or  glass 
plate  is  placed  on  the  baseboard  after  exact  focus  has  been  obtained 
on  another  focusing  plate.  When  unexposed  positive  film  is  used  in 
the  Eldia  Printer,  the  top  plate  of  the  printer  is  clamped  shut  as  usual. 
However,  the  picture  is  projected  through  the  glass  plate  upon  the 
positive  film.  Before  making  the  exposure,  focus  the  negative  upon 


a  white  area  the  exact  size  of  the  Leica  negative  and  also  in  the  exact 
plane  of  the  film  in  the  printer.  A  block  of  wood  may  be  cut  for  this 
purpose  or  two  printers  may  be  used. 

Film  positives  may  also  be  made  by  using  the  Leica  camera  loaded 
with  positive  film  without  a  lens.  The  picture  is  focused  from  the 
enlarger  directly  into  the  camera  after  the  focal  plane  shutter  has  been 
set  at  time  exposure.  Once  the  correct  focus  and  position  have  been 
determined,  the  entire  strip  of  film  may  be  exposed.  A  thin  block  of 
wood  3%mm  thick  (the  exact  thickness  between  the  back  of  the  Leica 
and  the  face  of  the  pressure  plate)  may  be  used  for  focusing  the  image 
before  the  camera  is  placed  into  position.  The  face  of  the  wood  should 
be  painted  white  and  the  exact  frame  size  of  the  picture  ruled  off  in 
black  crayon  for  a  guide  when  focusing. 

A  single  frame  IS  x  24mm  film  positive  may  be  made  by  reduc- 
tion from  the  Leica  size  24  x  36mm  negative.  The  Eldia  Printer 
equipped  with  a  single  masking  window  may  be  used  for  this  purpose. 
The  Leica  Enlarger  is  equipped  with  a  6cm  extension  tube  between 
the  50mm  lens  and  the  focusing  mount.  In  this  way,  it  is  easy  to 
reduce  the  Leica  negative  to  single  frame  size.  All  Leica  projectors 
are  equipped  for  single  frame  as  well  as  double  frame  projection.  As 
there  are  many  projectors  available  for  single  frame  pictures  only, 
this  method  of  making  positives  will  naturally  be  of  great  value  for 
such  projectors. 

"When  using  the  2x2  inch  glass  plates,  it  is  simpler  to  place  one 
of  the  undeveloped  plates  on  the  paper  easel  of  the  enlarger.  The 
plate  may  be  pushed  into  the  corner  of  the  easel  in  such  a  way  that  a 
second  plate  may  be  replaced  after  the  image  has  been  centered  on  the 
focusing  plate  which  contains  a  penciled  outline  1  x  iy2  inches  in  size, 
representing  the  size  of  the  Leica  negative.  If  preferred,  the  picture 
area  may  be  made  3  x  4cm  in  size  and  later  the  picture  masked  off 
by  using  the  short  strips  of  lantern  slide  binding  tape.  This  3  x  4cm 
size  can  be  projected  only  in  the  Udimo  projectors. 

An  orange  filter  is  convenient  to  use  while  making  glass  slides. 
Such  a  filter  may  be  thrown  across  the  projected  negative  image  in 
order  to  make  certain  that  the  unexposed  glass  plate  is  properly  cen- 
tered before  the  exposure  is  made. 

The  important  part  of  the  Leica  negative  is  easily  centered  upon 
the  glass  plate.  All  the  unessential  parts  of  the  negative  are  eliminated 
because  the  projected  picture  may  be  made  larger  or  smaller  in  order 
to  eliminate  certain  parts  of  the  negative.  At  the  same  time,  it  is  not 
difficult  to  shade  part  of  the  picture  during  exposure  in  order  to  bring 


Making  Positives 

out  certain  parts  of  the  positive,  sudi  as,  a  dense  sky,  or  possibly  some 
other  portion  of  the  negative  may  have  a  strong  highlight  which  should 
be  printed  longer.  In  fact  the  projection  method  of  making  glass  slide 
positives  is  the  Ideal  way  in  order  to  insure  the  best  results. 

In  some  cases,  it  is  necessary  to  make  3^/4  x  4  Inch  standard  lantern 
slides  for  use  in  the  larger  projectors.  Such  slides  are  made  by  using 
the  Lelca  enlarger  and  following  similar  methods  which  apply  to  the 
smaller  2x2  inch  glass  slides.  If  the  original  Lelca  negative  is  de- 
veloped properly,  It  is  possible  to  make  314  x  4  inch  glass  slides  which 
will  produce  beauty  and  brilliance  equal  to  slides  made  from  larger 
negatives  when  projected. 

When  using  the  Valoy  or  Focomat  enlargers  for  making  film  or 
glass  positives,  it  is  necessary  to  use  either  a  3cm  or  6cm  extension 
tube  between  the  50mm  lens  and  the  focusing  mount  of  the  enlarger. 
When  the  3cm  tube  is  used,  keep  the  lens  barrel  pulled  out  and  locked 
in  position.  However,  in  case  the  6cm  tube  is  used  the  lens  barrel  may 
be  pushed  in  as  far  as  it  will  go.  The  correct  focus  is  obtained  by 
turning  the  focusing  mount  of  the  enlarger.  Naturally,  other  extension 
tubes  or  any  combination  of  tubes  may  be  used  depending  upon  the 
results  required.  In  case  a  longer  working  distance  is  required  be- 
tween the  lens  and  the  positive,  a  6cm  tiibe  and  the  90mm  Elmar  lens 
may  be  used  very  successfully. 

Fig.  152  Laver  Combination  Print- 
er. A  complete  Unit  Easily  Con- 
vertible for  Contact  Printing  on 
Paper,  Paper  Strips,  Film  or  Glass 

Operating  the  Combination  Professional  Printer 

When  a  more  universal  positive  printing-  outfit  is  required,  the  Laver 
Combination   Printer    is    recommended.      The    Important    features    of   this 
printer  are  listed  as  follows: 
1.    Single  frame  and  double  frame  film  slides  may  be  made. 


2.  Single  frame,  Leica  size  double  frame,  3  x  4cm  and  4  x  4cm  glass  plate 
positives  may  be  made  by  using  a  supplementary  plate  printing  attach- 

3.  All  metal  construction,  with  enclosed  lamp  housing,  containing  a  15- 
watt  bulb  for  making  the  exposures. 

4.  Rheostat  control  for  varying  light  intensity. 

5.  A  small  red  light  burns  continually  in  the  lamp  housing  in  order  to 
show  the  proper  exposure,  or  density  of  each  negative. 

6.  Contact  button  for  turning  on  the  white  light  for  making  the  exposure. 

7.  Slots  on  each  side  of  the  printer  permit  the  insertion  of  a  thin  piece 
of  cardboard  for  use  in  shading  parts   of  negatives   during  the  ex- 

8.  Film  housing  will  hold  up  to  35  feet  of  positive  film.    The  exposed  film 
may  be  cut  off  and  developed  as  used. 

9.  On  each  side  of  the  glass  plate,  under  the  negative,  there  is  a  small 
line  drawing,  showing  which  way  the  negatives  should  be  printed  in 
order  to  appear  in  the  finished  positive  film  roll  in  the  proper  upright 
or  horizontal  positions. 

10.  When  the  positive  film  chamber  is  moved  out  of  position,  a  metal  plate 
automatically  covers  the  exposed  portion  of  the  positive  film.  Naturally 
the  printing  should  be  done  under  a  red  safety  light  in  the  darkroom. 

The  positive  film  is  loaded  into  the  Laver  Printer  by  removing  the 
top  portion  of  the  film  housing  and  rolling  the  film  directly  upon  the 
spool  opposite  to  the  ratchet  spool,  similar  to  the  one  in  the  Bldia 
Printer.  Make  certain  that  the  film  is  wound  with  the  emulsion  side 
out  when  loading  and  attach  the  free  end  to  the  take-up  spool  which 
is  wound  in  such  a  way  that  the  film  emulsion  will  be  on  the  inside. 
In  other  words,  the  film  passes  over  the  ratchet  wheel  and  down  under 
the  take-up  spool.  As  the  film  is  advanced,  a  distinct  click  will  be 
heard  for  each  single  frame  space.  Two  of  these  clicks  represent  the 
length  of  a  Leica  negative.  After  the  film  has  been  inserted,  place 
the  upper  part  of  the  housing  back  into  position. 

The  making  of  film  and  glass  slides  by  contact  printing  is  carried 
out  by  methods  similar  to  those  previously  explained. 

In  using  either  the  film  slide  attachment  or  the  glass  slide  attach- 
ment on  the  Laver  Printer,  it  is  possible  to  see  picture  numbers  or 
special  marks  which  may  be  made  on  the  film  margins  for  reference 
when  selecting  the  proper  negative  for  making  the  positive  printing. 

Using  the  Belun  Attachment 

Still  another  method  of  making  positives  is  by  using  the  Belun  1 :1 
copy  attachment.  For  this  set-up  secure  a  light  box  for  illuminating 
the  negative  which  is  to  be  copied  directly  upon  the  positive  film  which 
has  been  loaded  into  the  Leica  camera.  A  15-watt  bulb  will  be  sufficient 
for  illumination.  Set  the  Belun  copy  attachment  over  each  negative 
to  be  copied  and  make  the  exposures.  A  few  test  exposures  should  be 


Making  Positives 

made  before  running  through  the  entire  film.  A  short  length  of  posi- 
tive film  may  be  loaded  into  the  camera  for  making-  the  test  shots. 
By  using  the  Belun  attachment  sections  of  larger  negatives  can  be 
copied  and  made  into  positive  film  slides  for  projection  also.  Then 
by  using  the  Sliding  Focusing  Copy  Attachment  any  sized  negative  can 
be  copied  for  positive  film  slides. 

Fig.  153     My  Friend  Lionel 

Henry  M.  Lester 


Fig.  155    Sky  Kockets 

Elmar  50mm  lens,  wide  open,   1  minute  exposure 


E.  Scott  Pattison 


After  the  positive  film  or  glass  slide  lias  been  made,  the  next  step 
is  to  show  the  finished  pictures  on  a  projection  screen.  In  doing  this, 
it  is  necessary  to  select  one  of  the  projectors  described  later  in  this 

By  projecting  Leica  pictures,  you  have  an  opportunity  to  show 
one  picture  to  a  group  of  friends  wTho  may  be  assembled  for  the  occa- 
sion. In  this  way,  all  can  be  united  in  viewing  one  picture  at  a  time 
and  also  in  talking  about  each  picture  as  it  is  shown.  Thus,  a  very 
profitable  half  hour  or  an  entire  evening  may  be  spent.  Each  pic- 
ture is  thus  presented  in  its  fullest  advantages  of  large  size  and  with 
its  three  dimensional  effects  which  come  nearest  to  interpreting  the 
original  scene. 

In  the  field  of  visual  education  and  industrial  selling,  the  use  of 
positive  pictures  for  projection  is  of  immense  value.  In  the  industrial 
sales  field,  for  example,  it  is  possible  to  use  the  Lelca  Camera  to 
photograph  actual  manufacturing  processes  and  later  arrange  these 
pictures  in  slide  form  for  projection.  For  example,  there  is  a  largo 
industrial  firm  which  uses  the  Leica  Camera  very  successfully  by 
collecting  the  latest  developments  and  uses  for  their  product  from 
different  state  managers.  These  pictures  are  then  assembled  and 
printed  along  with  appropriate  titles  on  film  strips.  The  duplicate 
strips  are  later  mailed  out  to  the  various  branches  for  the  regular  sales 
meeting  of  the  district  salesmen.  Thus  each  district  is  kept  in  con- 
stant touch  with  all  the  developments  throughout  the  country. 

The  Various  Projectors  Available 

There  are  five  different  Leica  projectors  available  for  showing 
Leica  positives.  These  projectors  range  from  the  small  Umino  pro- 
jector to  the  large  400-watt  Udimo  projector.  In  selecting  the  proper 
equipment  for  your  purpose,  it  is  important  to  consider  the  various 
specifications  of  each  projector.  Two  of  the  most  generally  used 
projectors  are,  the  small  miniature  Umena  Projector,  and  the  Udimo 
100  Projector.  The  Udimo  250  and  Udimo  400  projectors  are  of 


special  value  for  use  in  projecting  natural  color  pictures  and  also  for 
use  in  larger  rooms  where  a  longer  projection  distance  is  required. 

Fig.  156  Udimo  - 100  Projector, 
Shown  Complete  with  Camera  Lens, 
Film  Magazines  and  Transport 

The  Udimo  100  Projector 

The  Udimo  100  Projector  is  considered  to  be  the  standard  model 
projector  which  is  used  by  many  Leica  owners.  The  specifications 
and  directions  for  using  this  projector  are  given  as  follows : 

1.  Height,  9*/2  inches,  width  of  base,  5  inches,  length  of  base,  IVs  inches. 

2.  Bayonet  socket  for  holding  100-watt  prefocused  projection  bulb. 

3.  Detachable  heat  absorption  screen.     When  glass  slides  are  being  pro- 
jected, this  heat  filter  may  be  removed,  thus  slightly  increasing  the 
brightness  of  the  screen  picture. 

4.  The  condenser  of  this  projector  is  made  up  of  three  elements,  the  front 
element  being  interchangeable  for  use  with  lenses  of  various  focal 
lengths.     This  system  insures  the  full  illumination  of  every  picture 
projected  with  the  various  lenses  providing  the  proper  front  condenser 
is  in  position.     Complete  information  about  the  interchangeable  con- 
densers is  given  later. 

5.  The  top  cover  plate  of  the  projector  housing  may  be  removed  when  the 
tubular  projection  lamp  is  to  be  changed.     When  removing  the  lamp, 
simply  pull  directly  out  of  the  socket.     When  placing  a  new  lamp  in 
position,  make  certain  that  the  filaments  are  parallel  with  the  condenser 

6.  The  entire  lamp  mounting  may  be  removed  by  turning  the  projector 
up-side-down  and  removing  the  three  large  screws  which  hold  the  bot- 
tom plate  in  position.    In  case  the  central  lamp  housing  is  out  of  align- 
ment, proper  centering  may  be  done  by  adjusting  the  set  screws  on 
the  base  plate. 

7.  The  intensity  of  the  projected  positive  is  increased  by  means   of  a 
mirror  reflector  mounted  at  the  rear  of  the  projection  lamp. 

8.  The  film  slide  attachment  which  is  mounted  on  the  front  part  of  the 
projector  may  be  rotated  in  order  to  show  horizontal  and  vertical  pic- 
tures  in   their   proper   orientation.     There   is   a   small    spring    catch 
mounted  just  above  the  revolving  attachment.    This  catch  may  be  re- 



leased    when   the   attachment   is   changed   to   a  vertical   or   horizontal 

9.  The  various  slide  masks  may  be  used  for  showing  film  or  glass  slide 
positives  in  various  sizes,  from  single  frame  up  to  4  x  4cm.  All  these 
masks  and  slides  are  quickly  interchangeable  in  the  film  or  glass  slide 
attachment  which  is  mounted  in  front  of  the  projector  and  secured  into 
position  with  four  knurled  knobs. 

10.  AH  the  Leica  lenses  with  the  exception  of  the  35mm  wide  angle  may 
be  used  with  this  projector  as  well  as  the  Udinio-250  and  Udimo-400 
Projectors.     There  are  also  two  special  80mm  and   120nim  projection 
lenses  available  for  these  projectors.    A  special  base  tube  or  receiving 
socket  is  used  with  the  80mm  and  120mm  projection  lenses  for  attach- 
ing to  the  projector.    All  the  Leica  lenses  are  screwed  into  the  film  or 
glass   slide  attachment  directly  without  the  use   of  any  intermediate 

11.  When  loading  the  positive  film  slide  into  the  Udimo  film  slide  attach- 
ment, proceed  as  follows: 

a.  While  facing  the  projector  from  the  front,  remove  the  left  film 
drum  and  draw  out  the  film  transporting  gate.     Make  certain 
that  this  gate  is  thoroughly  cleaned.     The  front  plate  may  be 
removed  by  lifting  out  from  under  the  two  springs  which  hold 
it  into  place.    At  the  same  time,  the  lower  glass  plate  may  be 
slid  to  one  side  and  removed  by  slightly  raising  the  spring  band 
which  will  be  seen  along  the  top  side  of  the  film  gate.     This 
plate  may  be  replaced  by  a  plate  with  single  frame  window  In 
case  single  frame  film  slides  are  to  be  used.    Otherwise,  clean 
the  original  plate  and  place  it  back  in  position  along  with  the 
film  transport  gate. 

b.  When  replacing  the  film  transport  gate,  push  it  into  its  slide- 
way  as  far  as  it  will  go.     While  facing  projector,  this  gate  Is 
pushed  into  position  from  the  left  side,  the  same  side  through 
which  the  positive  film  strips  are  started. 

c.  Replace  the  left  film  housing  and  insert  the  positive  film  roll 
into   this   housing   with    the  beginning   of   the   roll   projecting 
through  the  guide  which  opens    directly  into  the  film   sliding 
gate  and  is  transported  through  this  gate  by  turning-  the  ratchet 

d.  The  turning  knob  of  this  ratchet  wheel  must  be  pressed  down 
each  time  the  film  is  transported,  otherwise,  the  film  will  not 
turn.     After  the  film  has  been  transported,  raise  the  turning 
knob.     In  doing  this,  the  glass  pressure  plate  automatically 
presses  against  the  film  and  holds  it  in  a  perfect  plane  during 
the  projecting.    When  the  turning  knob  is  depressed,  this  glass 
plate  automatically  separates  at  the  same  time  the  film  is  being 
transported.     This  precaution  prevents  any  possible  scratching 
of  the  film. 

e.  As   the   film   is   turned   through   the   transport   gate,    it   auto- 
matically enters  the   opposite  film  chamber  on  the  right  and 
winds  into  this  chamber. 

f .  Start  the  positive  film  through  the  transporting  device  with  the 
emulsion  side  facing  the  projection  bulb  being  sure  that  the 
horizontal  images  of  the  film  are  inverted  or  upside  down. 


12.  There  are  four  interchangeable  condensers  for  use  with  the  three  Udimo 
Projectors.     These  condensers  are  supplied  for  use  with  the  various 
lenses  of  different  focal  lengths.     Each  condenser  has  marks  on  the 
side,  indicating  the  focal  length  of  lenses  required  for  the  particular 
condenser.     The  exact  specifications  of  each  condenser  are  given  as 
follows : 

a.  Interchangeable  Condenser  marked  "5"  for  use  with  Summar, 
Hektor  and  Elmar  50mni  lenses,  for  use  with  Udinio  100  and 
Udimo  300  Projectors. 

b.  Interchangeable  Condenser  marked  "5VIIK"  for  use  with  Sum- 
mar,  Hektor  and  Elmar  50mm  lenses  for  Udimo  400  Projector 

c.  Interchangeable  Condenser  marked  "7.3-8-9"  for  use  with  Leica 
lenses  Hektor  73mm,  Elmar  90mm,  and  special  projection  lens 
Milar  80mm  focus. 

d.  Interchangeable  Condenser  marked  "10.5-12-13.5"  for  use  with 
Leica  lenses  Elmar  105mm,  Elmar  135mm  and  special  projec- 
tion lens  Dimax  120mm  focus. 

13.  The  special  120mm  projection  lens  is  known  as  the  Dimax,  while  the 
80mm  special  projection  lens  is  known  as  the  Milar. 

14.  The  Glass  Slide  Changer  as  illustrated  is  excellent  for  use  when  show- 
ing" the  2x2  inch  glass  slides  in  the  Udimo  Projectors.     This  Slide 
Changer  may  be  used  in  the  special  glass  slide  holder,  or  it  may  be 
used  in  the  Film  Slide  Attachment  after  the  two  film  drums  have  been 

Fig.  157  Udimo-250  Projector.  Illus- 
tration Shows  Lamp  Housing  Only. 
All  attachments  are  Interchangeable 
with  the  Various  Udimo  Projectors 

Fig.  158  Udimo-400  Projector. 
Illustration  Shows  Lamp  Housing 



Pig.  159  Glass  Slide  At- 
tachment, Interchangeable 
for  all  Udimo  Projectors 

Fig.  160  Glass  Slide 
Holder,  Interchangeable 
for  all  Udimo  Projectors 

All  the  film  and  glass  slide  attachments  are  interchangeable  for 
use  on  the  Udimo  100,  Udimo  250  and  Udimo  400  projectors.  The 
main  differences  in  these  projectors  are  in  the  lamp  housings.  100, 
250  and  400-watt  projection  bulbs  are  used  respectively  in  each  Udimo 
Projector.  The  height  of  the  Udimo  250  Projector  is  11%  inches, 
while  the  width  of  the  base  is  6  inches  and  the  length  9  inches.  The 
Udimo  250  has  a  special  self-contained  heat  filter  in  the  condenser 
system.  The  height  of  the  Udimo  400  Projector  is  12%  inches,  while 
the  width  of  the  base  is  7%  inches  and  the  length  13%  inches.  The 
Udimo  400  Projector  is  equipped  with  a  special  water  cooling  jacket 
which  should  be  filled  with  distilled  water  before  using. 

Fig.  161  Base  Tube  for  At- 
taching1 Special  80mm  and 
120mm  Projection  Lenses,  In- 
terchangeable for  all  Udimo 

Fig.  162  Film  Transport  Gate, 
Interchangeable  for  all  Udimo 


A  special  Elevator  Plate  may  be  attached  to  any  of  the  Udimo 
Projectors.  There  are  two  small  threaded  holes  in  the  base  at  the 
front  of  each  projector  for  attaching  the  Elevator  Plate.  This  Eleva- 
tor Plate  may  be  attached  to  the  base  of  either  projector  and  set  at 
the  proper  position  so  that  the  projected  picture  is  perfectly  centered 
on  the  projection  screen.  The  film  and  glass  slide  attachments  are 
all  interchangeable  for  the  various  projectors. 

Table  showing  screen  areas  for  various  projection  lenses. 
Screen  Distance  and  Screen  Areas  in  Feet 

Lens  6ft.        9ft.        12ft.       15ft.       18ft.       21ft.       24ft. 

Elmar  f:3.5  50m 

Hektor  f  :2.5  50m 3.9X2.7     6X3.9  8.1X5.4 

Summar  f:2  50mm 

Hektor  f  :1.9  73m 4.5X3     5.7X3.9  7.2X4.8     6X9 

Eimarf:490mm 3.6X2.4  4.5X3     5.7X3.9  6.6X4.5  8.1X5.4 

Elmar  f:6.3  105mm....  3.9X2.7  5.1X3.3  6.3X4.2  7.2X4.8   8.1X5.4 

Elmar  f:4.5  135mm..,.  3X2      3.6X2.44.5X3      5.4X3.6    6.3X4.2 

Milar  80mm 3.9X2.7  5.4X3.6  6.3X4.2  8.1X5.4  6.3X9.5   7.2X10.8 

Dimax  120mm   3,6X2.4  4.2X3.7  5.4X3.6  6.3X4.2   7.2X4.8 

Pig.  163  Udimo-750  Projector  complete  with  250mm  pro- 
jection lens  and  special  film  transporting  device 
which  accommodates  film  lengths  up  to  70  feet 

The  Udimo-750  Projector 

The  Udimo-750  Projector  is  really  a  universal  projector  which 
can  be  used  for  screen  distances  between  10  and  100  feet  or  more. 
All  the  Leica  lenses  with  the  exception  of  the  28mm  and  the  35mm 
can  be  used  with  this  750-watt  projector.  In  addition,  there  are  the 
80,  120,  150,  200,  and  250mm  projection  lenses  to  select  from.  The 
high  light  intensity  makes  it  possible  to  project  color  pictures  upon 
a  large  screen  and  still  retain  the  brilliance  required. 



There  are  six  different  interchangeable  condensers  available  for 

all  the  various  projection  lenses.     The  three  additional  condensers 
not  listed  on  page  240  are  added  as  follows : 

e.  Interchangeable  Condenser  marked  "15"  for  use  with  the  150mm 
Dimax  projection  lens. 

f.  Interchangeable  Condenser  marked  "2CFy  for  use  with  the  200mm 
Dimax  projection  lens. 

g.  Interchangeable  Condenser  marked  "25"  for  use  with  the  250mm 
Dimax  projection  lens. 

As  a  supplement  to  the  table  on  page  242  the  following  projection 
distances  and  screen  areas  will  give  additional  information  of  value: 

Lens  35  ft.  60  ft.  80  ft,  100  ft. 

Dimax  150mm 6X9         10      X  14% 

Dimax  200mm 7%  X  11  %         10  X  14% 

Dimax  250mm 6X9  8X12  10X14% 

All  measurements  are  given  in  feet 

The  Udimo-750  has  a  special  heat  filter  and  water  jacket  cooling- 
chamber  to  prevent  the  overheating  of  positive  films  during  projec- 
tion. All  the  interchangeable  accessories  used  with  the  other  Udimo 
projectors  may  also  be  used  with  the  Udimo-750.  A  special  film 
attachment  may  be  used  which  accommodates  all  film  lengths  up  to 
75  feet. 

Fig.  164    The  Umino  (50  watt)  or  Umena  (100  watt)  Miniature  Projector 
for  Single  and  Double  Frame  Film  Slides  or  Glass  Lantern  Slides 

The  Umino  and  Umena  Miniature  Projector 

One  of  the  simplest  and  most  compact  projectors  available  for 
showing  Leica  film  or  glass  positives  is  known  as  the  Umino  Projector 
which  contains  a  50- Watt  projection  bulb.  This  projector  is  so  small 
that  it  can  easily  be  carried  in  a  brief  case  along  with  a  supply  of 
positive  film  or  slides.  As  this  projector  has  so  many  distinct  ad- 


vantages,  it  Is  recommended  for  use  by  all  Leica  users  who  are  inter- 
ested in  projecting  their  pictures.  When  the  Umino  projector  is 
equipped  with  a  100-Watt  projection  bulb  it  is  referred  to  as  the 
Umena  Projector.  The  specifications  and  directions  for  using  this 

projector  are  given  as  follows : 

1.  Height  5  1/2  inches,  length  7  inches,  width  2  1/2  inches,  weight 
2  1/3  Ibs. 

2.  80mm  projection  lens  in  focusing  mount,  50  or  100-watt  projection 

bulb  available. 

3.  Six-volt  bulb  may  be  used  with  ordinary  automobile  storage  bat- 
tery when  the  usual  electric  current  is  not  available. 

4.  Front  film  housing  may  be  rotated  for  showing  vertical  or  hori- 
zontal pictures  after  loosening  the  set  screw  No.  1.    The  complete 
front  rotating  portion  of  the  projector  may  be  removed  after 
loosening  the  set  screw  No.  8.    After  this  set  screw  is  loosened, 
simply  raise  the  front  attachment  and  remove  from  its  position. 

5.  When  a  100-watt  bulb  is  used,  a  heat  absorption  filter  is  inserted 
into  position  as  indicated  by  No.  5.    A  spiral  spring  No.  4  is  re- 
moved or  replaced  for  holding  the  heat  filter  in  its  proper  position. 

6.  In  case  the  condensers  No.  6  and  No.  7  are  to  be  removed  for 
cleaning,  it  it  only  necessary  to  remove  the  spiral  springs  which 
hold  them  in  place. 

7.  When  loading  the  strip  of  positive  film  into  the  Umino  Projector, 
unhook  the  clamp  No.  11  and  swing  out  the  pressure  plate  No. 
12.     The  film  roll  may  be  inserted  into  the  film  chamber  No.  34, 
while  the  free  end  of  the  film  roll  is  passed  down  under  the  metal 
guide  of  the  lower  chamber.    After  making  certain  that  the  per- 
forations of  the  film  mesh  with  the  cogs  on  the  turning  rachet 
wheel,  close  the  hinged  pressure  gate  No.  12. 

8.  After  the  film  has  been  placed  in  its  proper  position,  turn  the  film 
transporting  knob  No.  20  slowly  until  the  first  frame  of  the  film 
strip  comes  into  exact  position  on  the  projection  screen.     This 
frames  the  first  picture  and  from  then  on  the  knob  is  pulled  out 
and  turned  for  each  picture.    A  slight  click  is  heard  as  the  knob 
is  turned.    Each  click  represents  a  space  of  a  single  frame  positive, 
thus  two  clicks  are  necessary  to  place  each  Leica  size  positive  in 

9.  When  2x2  inch  glass  slides  are  to  be  used,  the  front  film  pressure 
plate  No.  12  is  removed.    In  doing  this,  simply  unscrew  the  knob 



No.  17  part  way  until  the  cross  plate  No,  IS  separates  from  the 

glass  pressure  plate  No,  12.  Then,  remove  the  glass  plate  entirely. 
Next,  draw  out  the  back  glass  pressure  plate  X5.  0.  In  this  way 
space  is  left  for  Inserting  the  2x2  inch  glass  slides  which  may  be 
pushed  through  as  required.  "When  using  the  glass  plates  it  is 
not  necessary  to  revolve  the  front  housing  because  the  glass  plates 
have  the  pictures  already  mounted  in  either  horizontal  or  vertical 

10.  When  changing  the  projection  bulb,  loosen  the  set  screw  No.  10 
and  then  raise  and  remove  the  lamp  housing  No.  9.  The  interior 
metal  lamp  housing  is  pushed  back,  thus  leaving  the  projection 
bulb  free  for  changing. 

Fig.  165  Cross  section  of 
Umino  or  Umena  Minia- 
ture Projector,  Showing 
Detail  of  Optical  System 

Fig,  166  Cross  sec- 
tion of  Umino  or 
Umena  Miniature  Pro- 
jector, Assembled, 
Ready  for  Projection 

When  using  the  Umino  Projector,  make  certain  that  the  film 
positives  have  been  hardened  in  order  to  prevent  scratching  during 
projection.  If  the  positives  have  been  properly  processed,  danger  of 
scratching  the  film  slides  during  projection  will  be  practically  elim- 


Titles  for  Film 

Whenever  possible,  try  to  include  printed  titles  in  your  film 
strips.  A  few  titles  scattered  through  a  film  strip  will  give  added  in- 
terest as  well  as  information  to  the  people  who  are  viewing  pictures. 
The  strip  can  start  with  a  special  title  and  short  description  about 
what  the  pictures  will  cover.  Titles  are  easily  made  by  using  one 
of  the  copy  attachments  referred  to  in  the  chapter  on  Copying  with 
the  Leica  Camera.  Boards  containing  movable  letters  are  available 
for  setting  up  titles. 

If  a  title  board  cannot  be  secured,  simply  use  a  black  slate  and 
letter  the  wording  with  chalk.  Make  the  photograph  and  then  erase 
the  lettering  for  the  next  sub  title.  In  fact,  titles  might  even  be  let- 
tered across  actual  Leica  enlargements  which  may  present  an  interest- 
ing background.  With  a  lettering  board  many  interesting  titles  may 
be  worked  up  for  use  with  your  film  slides. 


Rudolf  Hoffmajin 


Storing  Positive  Pictures 

All  film  slides  and  glass  slides  should  be  kept  in  containers  free 
from  dust.  Such  containers  may  be  secured  from  the  regular  photog- 
raphic dealers,  or,  if  preferred,  special  containers  can  be  made  to  cover 
any  individual  requirements.  The  small  metal  cans  with  covers  on 
which  the  titles  of  the  film  slides  may  be  written  are  excellent.  These 
tins  may  be  purchased  on  the  market.  Another  way  to  keep  film  slides 
is  by  using  the  regular  film  storage  boxes  which  contain  cross-sections 
with  spaces  for  about  25  rolls  of  film.  The  glass  slides  are  easily  kept 
in  small  boxes  with  hinged  lids. 

As  your  film  and  glass  slide  library  grows,  it  will  be  necessary  for 
you  to  develop  a  special  indexing  system  so  that  any  picture  may  be 
located  instantly  when  desired.  In  the  case  of  film  slides,  it  is  con- 
venient to  make  paper  contact  prints  of  every  picture  on  a  single 
strip  of  film.  These  contact  pictures  are  then  mounted  onto  an  index 
card  which  contains  titles,  numbers  and  complete  information  about 
that  particular  film  roll.  Contact  prints  of  the  individual  glass  slides 
may  also  be  made  and  mounted  on  individual  indexing  cards,  along 
with  the  proper  title  and  descriptions.  In  the  case  of  the  glass  slides, 
it  is  very  easy  to  group  the  subjects  under  various  classifications,  such 
as,  buildings,  street  scenes,  birds,  boats,  portraits,  flowers,  or  any  other 
subject.  As  the  glass  and  slide  collection  grows,  a  valuable  index  and 
cross  reference  system  may  be  built  up.  The  slides  are  then  available 
for  instant  use  for  showing  in  the  home  or  in  preparing  special  lec- 
tures or  demonstrations. 


Distance  in  feet 
between  Umino  or 

Umena  and  Screen  Image  Screen  Image 

projection  screen  Leica  size  single  frame  size 

6  2  ft.     5  in.  x  1  ft.  7  in.         1  ft.     7  in.  x  1  ft     3  in. 

9  3  ft.     7  in.  x  2  ft.  3  in.         2  ft.     3  in.  x  1  ft.     8  in. 

12  4  ft.  10  in.  x  3  ft.  2  in.         3  ft.     2  in.  x  2  ft.     5  in. 

15  6  ft.  x  3  ft.  10  in.         3  ft.  10  in.  x  3  ft. 

18  7  ft,     2  in.  x  4  ft.  8  in.         4  ft.     8  in.  x  3  ft.     6  in. 

21  8  ft.     4  in.  x  5  ft.  6  in.         5  ft.     6  in.  x  4  ft.     2  in. 

24  9  ft.     G  in.  x  6  ft.  3  in.         6  ft.     3  in.  x  4  ft.     8  in. 


Fig.  168     Dachshunds 
(Not  a  Stereo!) 

Ivan  Dmitri 



Our  keen  appreciation  of  realism  in  photography  finds  its  fullest 
expression  in  our  fondness  for  color  pictures  and  stereoscopic  views. 
The  latter,  known  among  graphic  arts  as  three  dimensional  photogra- 
phy, is,  for  the  time  being  the  only  method  of  rendering  pictures  so  that 
the  subject  looks  round  and  plastic.  It  is  unfortunate  that  at  present 
we  are  unable  to  lend  this  plasticity  to  single  picture  views  obtained 
by  ordinary,  two  dimensional  photography,  which  always  has,  and 
still  is  endeavoring  to  assist  our  imagination  to  see  things  in  pictures 
as  we  are  accustomed  to  see  them  in  life.  By  means  of  lighting, 
suitable  backgrounds  and  skillful  placement  of  the  object  within  its 
environment,  photographers  are  trying  more  or  less  successfully  to 
give  their  pictures  the  effect  of  roundness  and  depth.  But  so  far, 
photography  has  not  been  able  to  find  a  substitute  for  that  lifelike 
rendering  of  depth  in  anything  but  the  double  image  secured  by  view- 
ing the  subject  from  two  points. 

There  is  nothing  new  about  a  stereo  camera.  But  the  manner  in 
which  stereo  views  are  obtained  with  a  Leica  camera  is  a  decided 
departure  from  the  old-fashioned  methods  of  stereo  photography. 
Before  the  Leica  made  its  entrance  into  this  field,  a  stereo  camera  had 
to  have  two  lenses.  In  better  cameras  of  this  type  these  lenses  had 
to  be  of  the  matched  type,  synchronized  as  to  lens  aperture  and  shut- 
ter action.  The  stereo  feature  introduced  by  the  Leica  consists  of 
taking  stereo  pictures  with  one  lens  only. 

The  problem  was  solved  with  remarkable  simplicity.  Two  prisms, 
placed  about  70mm  apart  along  a  horizontal  axis  are  made  to  act  as 
small  periscopes,  bringing  the  two  respective  images  together  in  front 
of  the  regular  Leica  lens.  Each  of  these  two  images  enters  the  camera 
and  reaches  the  film  plane  through  its  respective  half  of  the  lens. 
Thus  two  separate  images  are  formed  upon  the  film,  each  measuring 
half  of  the  Leica  frame;  lSx24mm.  There  is  no  dividing  line  be- 
tween these  two  images :  they  merely  join  each  other,  forming  a  nar- 
row fade  into  one  another,  thus  using  the  maximum  space  available. 

A  negative  thus  formed  is  made  into  a  positive  transparency  by 
contact  printing  upon  35mm  positive  film  without  any  of  the  customary 


reversal  of  images.  The  positive  is  then  viewed  through  a  slightly 
modified  form  of  the  same  periscopic  double  prism,  where  the  process 
is  reversed.  Here  the  images  are  picked  up  from  the  double  frame 
separately,  and  carried  to  two  eyepieces,  thus  giving  full  stereo  effect. 

The  Leica  method  of  stereo  photography  has  also  the  advantage  of 
seeing  stereo  pictures  at  their  very  best  because  of  the  added 
luminosity,  plasticity  and  brilliance  of  viewing  positive  transparencies 
instead  of  paper  prints.  All  this  gives  the  picture  an  added  sense  of 
realism.  Of  course,  if  paper  prints  are  preferred,  they  may  be  made 
just  as  easily  by  enlargement  to  the  size  desired. 
The  Stereo  Equipment 

The  Stereoly  attachment  consists  of  two  units:  the  photographing  unit, 
which  is  placed  over  the  standard  50mm  lens,  and  held  in  place  by  means  of 
a  small  arm  fitting  into  the  camera  clip;  and  the  viewing-  unit,  which  has 
adjustable  eyepieces  and  a  slotted  channel  for  the  film.  The  viewing  unit 
can  be  held  in  hand  or  attached  to  a  convenient  stand.  The  Stereoly  taking 
unit  has  its  own  view  finder,  which  replaces  that  of  the  camera.  Since 
each  of  the  two  pictures  obtained  is  only  half  as  large  as  the  regular 
Leica  frame,  only  half  the  area  covered  by  the  50mm  lens  is  available. 
The  Leica ,  must  always  be  held  horizontally  when  used  with  the  Stereoly, 
which  will  result  in  two  vertical  images.  The  camera  should  not  be  used 

Fig.  170  Stereoly  Photographing 
Unit  for  Stereoscopic  Photography 
with  Hektor,  Elmar,  and  Summar 
50mm  Lenses  only 

Fig.  169  Stereo  Viewer, 
on  Stand,  for  35mm  Leica 
Stereo  Positives 

Fig.  171  Stereo  Slide  Bar,  for 
Stereoscopic  Photography  when 
making  two  separate  negatives 



Taking  Stereo  pictures  with  the  Leica  is  no  more  complicated  than 
taking  ordinary  pictures.  The  Stereoly  is  placed  before  the  lens,  given  a 
simple  adjustment  described  in  the  instructions  accompanying-  each  instru- 
ment, and  one  is  ready  to  take  pictures.  The  exposure  variation  of  the 
Stereoly  is  almost  negligible,  if  one  considers  the  latitude  of  modern  film 
emulsions.  To  be  sure,  the  exposure  factor  is  not  constant.  It  varies  from 
the  requirement  of  an  exposure  fifty  per  cent  longer  with  the  lens  set  at 
f:3.5  to  an  increase  of  some  ten  per  cent  only,  when  the  lens  is  stopped 
down  to  f  :12.5.  As  a  matter  of  general  practice,  it  is  recommended  to  take 
stereo  pictures  with  the  lens  stopped  down  to  f  :6.3  or  f:9.  Lens  openings 
larger  than  these  do  not  yield  sufficient  depth  of  focus  for  stereo  pictures, 
while  those  smaller  than  f  :9  are  apt  to  cause  vignetting  of  images  under 
certain  conditions.  The  Stereoly  unit  does  not  by  itself  cause  any  unsharp- 
ness  of  pictures,  but  to  avoid  pictures  lacking  definition  and  detail,  so 
important  in  stereos,  all  exterior  glass  surfaces  should  be  kept  scrupulously 
clean  at  all  times,  and  free  from  finger  marks  above  all. 

Filters  for  Stereo  Photography 

Filters  may  be  used  in  connection  with  the  Stereoly  attachment  if 
they  are  in  the  standard  Leica  slip-on  mount.  They  are  simply  placed  over 
the  lens,  and  the  Stereoly  is  attached  over  the  filter.  Since  the  aperture 
of  the  lens  cannot  be  changed  nor  can  the  filters  be  removed  without  first 
removing  the  Stereoly  from  the  camera,  it  is  suggested  that  the  lens  be 
operated  always  at  the  same  stop  when  used  for  stereo  pictures.  Filters 
should  be  used  as  judiciously  as  in  any  other  form  of  Leica  photography. 
It  should  be  remembered  that  filters,  as  their  name  implies,  are  not  there 
to  add  anything  to  the  pictures,  but  merely  to  remove  something  that  may 
be  objectionable.  Frequent  reference  to  the  special  chapter  on  this  subject 
may,  we  hope,  result  in  a  more  reserved  and  more  appropriate  use  of 
filters  in  general. 

In  certain  instances  where  special  filters  used  for  definite  effects  are 
not  available  in  Leica  mounts,  and  cannot  be  made  to  fit  on  account  of 
their  excessive  thickness,  they  may  be  used  (if  available  in  pairs)  by  being 
fastened  to  the  front  part  of  the  Stereoly  taking  unit  in  such  a  way  that 
they  completely  cover  the  two  front  apertures.  It  may  not  be  amiss  to 
say  that  when  this  is  resorted  to,  both  filters  must  be  identical. 

Sunshades  and  Film 

Experiments  have  shown  conclusively  that  stereo  pictures  secured  with 
the  aid  of  sunshades  were  quite  superior  to  those  obtained  without  them. 
They  seem  to  be  sharper,  clearer  and  more  brilliant  and  have  a  better  defini- 
tion throughout.  The  proverbial  ingenuity  of  Leica  users  should  find  here 
another  field  of  application.  The  writers  have  used  successfully  two  stand- 
ard Leica  sunshades  of  the  inexpensive  kind  fastened  to  each  end  of  the 
Stereoly  unit  by  means  of  scotch  tape.  On  another  occasion,  a  10  inch  length 
of  1%  inch  black  scotch  tape  wound  all  around  the  front  edge  of  the 
Stereoly,  protruding  about  an  inch,  served  the  purpose  admirably. 

Stereoscopic  photography  with  the  Leica  is  so  simple  that  it  may  be 
said  that  there  is  actually  no  difference  between  this  form  of  photography 
and  any  other  form  of  Leica  photography,  except  for  the  accessories  re- 
quired. For  this  reason  the  selection  of  film,  developer,  filters,  and  other 
factors  should  be  made  exactly  as  one  would  for  any  other  form  of  work. 
Fineness  of  grain  is  not  more,  but  certainly  not  less,  important  than  in  any 
other  form  of  Leica  photography.  Careful  handling  of  negative  material 
is  just  as  imperative.  Absence  of  scratches,  abrasion  marks,  reticulation 


and  all  other  proofs  of  carelessness  is  just  as  important  in  stereo  pho- 
tography as  it  is,  say,  in  portraiture. 

Selection  of  film  should  be  made  in  a  similar  way  to  that  of  ordinary 
photography.  Orthochromatic  film  of  fine  grain  should  be  preferred  by 
beginners,  and  those  who  are  not  accustomed  to  the  latitude  and  softness 
of  panchromatic  emulsions.  Those,  however,  who  know  and  like  panchro- 
matic films  will  prefer  them  for  stereoscopic  photography  just  as  they  do 
for  other  types  of  work, 

It  is  quite  feasible  to  produce  direct  stereo  transparencies  on  negative 
stock  by  reversal.  For  this  purpose,  the  newest  Agfa  film,  the  Eeversible 
Superpan  is  very  much  to  be  recommended.  Generally,  regular  negative 
materials  of  the  modern  type  cannot  be  used  for  reversal  on  account  of 
their  gray  nonhalation  backing.  However,  it  should  be  realized  that  although 
reversal  as  one  of  the  simplest  ways  for  securing  transparencies,  it  is  by 
no  means  the  most  practical  procedure:  through  reversal  one  loses  the  nega- 
tive, and  with  it  the  only  way  for  making  additional  prints.  After  reversing 
a  negative,  one  has  nothing  but  that  one  positive  on  hand,  and  production 
of  additional  positives,  while  not  impossible,  is  difficult  and  rather  compli- 
cated. Even  with  the  greatest  care,  positive  films  do  get  scratched  and 
damaged  in  handling  and  pulling  through  the  Stereo  Viewing  Attachment. 
Because  of  this  fact,  one  should  have  the  means  of  securing  another  positive 
print  easily  and  economically.  All  positive  transparencies  should  receive 
an  adequate  hardening  treatment  by  any  of  the  methods  described  in  the 
chapter  dealing  with  this  subject. 

Stereo  Color  Pictures 

As  far  as  black-and-white  photography  goes  stereo  transpar- 
encies represent  probably  the  most  realistic  form  of  reproduction. 
But  natural  color  transparencies  for  stereoscopic  viewing  mark  the 
goal  (at  least  at  present)  of  realism.  "With  the  advent  of  KODA- 
CHROME,  the  new  natural  color  film  recently  made  available  for 
the  Leica  camera  by  Eastman  Kodak  Company  direct  color  stereo- 
scopic photography  with  the  Stereoly  Attachment  is  not  only  prac- 
tical but  extremely  simple  and  easy.  No  color  filters  being  required 
for  use  with  Kodachrome  film,  there  being  one  type  of  film  for  day- 
light and  another  for  work  in  artificial  light — there  is  no  longer  any 
impediment  to  simply  attaching  the  Stereoly  to  one's  Leica,  stopping 
down  the  lens  and  proceeding  to  photograph  in  natural  color  as  one 
would  to  make  black-and-white  pictures.  Kodachrome  Haze  filters, 
if  one  wishes  to  use  them  for  distant  views,  should  be  used  according 
to  suggestions  made  on  the  preceding  page. 

The  handling  of  Kodachrome  films  is  described  in  a  special  chap- 
ter of  this  volume  (Chapter  14).  No  other  special  knowledge  nor 
equipment  is  necessary  to  secure  excellent  stereo  transparencies  in 
natural,  brilliant  colors  from  the  very  first  roll  of  Kodachrome  film 
used.  The  same  roll  of  film  can,  of  course,  be  used  for  both  stereo 
and  standard  pictures.  After  the  film  comes  back  from  processing 



the  respective  frames  are  cut  apart  and  mounted  either  for  projec- 
tion or  for  viewing  in  the  Stereoly  Viewing  Attachment. 

The  emulsion  speed  of  both  types  of  Kodachrome  Film  has 
recently  been  so  substantially  increased  that  perfectly  exposed  pic- 
tures are  easily  obtained  at  the  f  :6.3  aperture  recommended  for  work 
with  the  Stereoly  Attachment.  The  film  is  processed  by  Eastman 
Kodak,  the  cost  of  processing  being  included  in  the  original  purchase 
price  of  the  roll.  This  should  be  welcomed  by  many  miniature  cam- 
era workers  as  it  relieves  them  of  the  necessity  to  put  their  color 
films  through  a  tedious  and  rather  complicated  procedure. 

Protecting  the  Stereos 

Stereo  transparencies  of  any  intrinsic  value  that  cannot  be  dupli- 
cated should  be  handled  with  particular  care.  Any  stereo  transparency 
may  be  bound  between  two  thin  plates  of  cover  glass  and  thus  assured 
comparative  permanence  and  security  from  scratches,  abrasion  marks 
and  finger  marks.  This  precaution  would  apply  particularly  to  color 
transparencies,  where  negatives  are  not  available,  since  they  are  ob- 
tained by  means  of  reversal.  For  this  reason,  color  transparencies 
should  be  bound  in  glass  as  soon  as  they  are  dry  and  ready  for  viewr- 
ing.  One  has  the  choice  of  binding  them  into  individual  frames,  or, 
better  still,  into  strips  of  three  frames  each.  Special  cover  glass  plates 
are  available  for  this  purpose,  measuring  35mm  x  120mm,  and  their 
use  cannot  be  too  strongly  recommended,  not  only  for  color  transpar- 
encies, but  also  for  any  black  and  white  pictures  wrhich  are  worth  hav- 
ing. In  such  bound  form  they  become  comparatively  permanent  and 
most  convenient  to  handle  and  to  file. 

While  the  Stereoly  may  be  used  for  all  forms  of  stereo  photog- 
raphy, both  indoors  and  outdoors,  it  is  primarily  intended  for  work 
without  a  tripod,  for  action  pictures,  landscape  work,  and  all  such 
subjects  as  require  rather  short  exposures.  A  somewhat  simpler  acces- 
sory is  available  for  stereo  photography  of  still  life,  table  top  photog- 
raphy, three  color  separation  work,  etc.  This  accessory  is  known  as 
the  Stereo  Slide  Bar:  a  metal  bar  about  6  inches  long  with  an  en- 
graved scale  and  slide  mounted  upon  it.  By  means  of  a  set  screw 
the  slide  may  be  placed  anywhere  along  the  bar.  The  Stereo  Slide 
Bar  is  firmly  secured  to  a  rigid  tripod  either  of  the  field  or  table  top 
variety.  The  camera  is  fastened  to  the  slide  and  one  exposure  is  made 
with  the  camera  at  one  end  of  the  bar.  Then  the  camera  is  quickly 
moved  to  a  predetermined  position  at  the  other  end  of  the  bar,  and 


the  second  exposure  made.  Thus,  the  set  of  stereo  pictures  Is  secured 
upon  two  full  frame  negatives,  which  may  be  made  either  into  trans- 
parencies or  prints.  This  method,  while  not  as  universal  in  its  appli- 
cation as  the  Stereoly,  has  certain  advantages  over  the,  other.  The 
separation  of  the  two  shots  may  be  adjusted  to  suit  any  special  re- 
quirements, a  separation  up  to  6  inches  being  available  for  special 
effects.  Any  lens  and  any  filter  may  be  used  for  this  type  of  work.  The 
two  resulting  pictures  are  larger  than  those  available  with  the  Stereoly, 
but  they  cannot  be  viewed  through  the  regular  stereo  viewing  unit. 

The  Stereoly  unit  should  not  be  used  for  photographing  objects 
less  than  5  to  7  feet  from  the  camera.  Close  range  photography  in- 
troduces complications  of  parallax  adjustment,  since  the  optical  axes 
of  the  two  prisms  of  the  Stereoly  are  theoretically  parallel,  intersect- 
ing one  another  at  infinity.  For  this  reason,  photography  of  near 
objects  may  better  be  accomplished  with  the  aid  of  the  Stereo  Slide 
Bar,  into  which  the  parallax  adjustment  may  be  introduced  by  careful 

Using  Two  Cameras 

There  is  still  another  method  of  stereo  photography  feasible  with  the 
Leica  camera,  but  for  the  present,  it  remains  within  the  realm  of  experi- 
mental possibilities,  there  being  a  lack  of  specific  accessories  for  the  purpose. 
Such  accessories  would  have  to  be  produced  by  the  experimentally  minded 
worker,  conceived  by  his  own  ingenuity  and  adapted  to  his  specific  require- 
ments. This  new  method  is  mentioned  here  just  as  an  experimental  possi- 
bility for  whatever  it  may  be  worth. 

The  method  requires  the  use  of  two  Leica  cameras,  each  equipped  with 
the  same  type  of  lens.  It  makes  little  differences  which  two  lenses  are 
chosen  so  long  as  they  are  identical.  The  experiment  is  available  not  only 
to  those  fortunate  members  of  the  Leica  fraternity  who  own  two  cameras 
with  lenses  which  are  alike,  but  to  any  two  friends  who  desire  to  pool  their 
equipment,  work  and  experience  for  the  purpose  of  achieving:  interesting 

The  two  cameras  should  be  mounted  together  upon  some  rigid  mount 
in  such  a  manner  that  the  bottoms  touch,  while  the  lenses  face  in  the  same 
direction.  In  order  that  the  respective  lenses  be  on  the  same  level,  it  is 
necessary  to  have  one  of  the  cameras  slightly  higher  than  the  other.  With 
the  cameras  placed  in  this  manner,  operating  controls  on  the  outside  are 
easily  accessible.  Such  an  arrangement  is  quite  feasible  since  it  so  happens 
that,  with  the  bottoms  of  the  two  cameras  touching  each  other,  the  lenses 
are  about  65mm  apart.  This  provides  the  minimum  separation.  Greater 
distances  may  be  secured  by  placing  strips  of  cardboard  between  the  bot- 
toms of  the  cameras,  or  an  accurately  prepared  wedge  of  wood,  in  the 
event  that  a  parallax  adjustment  be  required  for  special  close  range  work. 

Once  these  cameras  are  correctly  assembled  in  a  comparatively  rigid 
unit,  their  operation  is  simple  and  effective.  Such  an  outfit  actually  exceeds 
the  Stereoly  method  in  flexibility  and  adaptability  for  special  work,  such  as 
close-up  work,  more  particularly  since  it  permits  the  use  of  interchange- 
able lenses,  filters,  and  parallax  adjustment. 



Each  of  the  two  cameras  should  be  equipped  with  the  Universal  View 
Finders,  which  also  have  the  parallax  adjustment,  and  exposures  might  be 
made  simultaneously,  either  by  hand  or  by  means  of  cable  releases.  A  truly 
de  luxe  method  of  operating  the  shutter  releases  would  be  provided  by  the 
Automatic  Release,  available  for  the  synchronized  operation  of  releases  of 
the  Micro  Ibs*b  Attachment,  employed  in  photomicrography. 

This  method  has  distinct  advantages  over  any  other  method  of  securing 
stereo  pictures  and  should  be  considered  seriously  by  all  desiring  to  obtain 
stereos  of  a  scientific  nature.  One  of  its  potential  advantages  is  the  ease 
with  which  the  parallax  adjustment  may  be  made,  an  adjustment  decidedly 
essential  for  the  correct  viewing  of  small  objects  photographed  at  close 

Depending  on  the  focal  length  of  the  lenses  employed  in  this  work, 
the  separate  pictures  will  have  some  overlap,  which  will  decrease  with  the 
increased  focal  length  of  the  respective  lenses.  At  all  events,  such  overlap 
may  easily  be  eliminated  in  making  the  prints  or  transparencies,  either  by 
means  of  masking  them  or  trimming  them  just  prior  to  mounting. 

Making  of  Stereo  Prints 

Regardless  of  whether  the  Stereoly  attachment  or  the  Stereo 
Slide  Bar,  or  the  two-camera  method  has  been  used  to  make  stereo 
negatives,  paper  prints  may  easily  be  produced  from  any  of  them. 
The  prints  may  be  of  the  contact  type,  but  a  much  better  job  will  be 
secured  by  making  enlargements. 

Enlargements  or  negatives  produced  with  the  Stereoly  attach- 
ment are  made  on  one  sheet  of  paper,  preferably  of  the  glossy  variety 
for  greater  brilliance  and  better  detail.  Before  a  print  is  made,  the 
available  stereo  viewing  equipment  should  be  examined  to  determine 
the  correct  size  of  the  finished  print.  It  will  be  found  to  be  most 
practical  to  enlarge  the  entire  frame  of  the  negative  and  trim  it  to 
the  required  size  afterwards.  Since  there  is  no  sharp  line  of  de- 
marcation between  the  two  halves  of  the  print,  they  should  be  cut 
in  half  carefully,  or  better  still,  left  together  unseparated,  and  thus 
mounted  on  a  piece  of  cardboard  of  a  size  conveniently  accommodated 
by  the  stereopticon. 

In  the  case  of  two  separate  negatives  obtained  by  the  other  two 
methods,  separate  enlargements  will  be  made.  It  is  important  that 
both  negatives  be  enlarged  to  identical  size,  with  the  enlarger  in  the 
same  position,  using  the  same  paper,  developer  and  exposures.  Fin- 
ished prints  should  be  trimmed  only  after  careful  examination  and 
tests  made  in  the  stereopticon.  These  prints  should  not  be  trimmed 
by  a  rule  of  thumb  to  include  similar  areas.  It  must  be  remembered 
that  each  picture  has  been  secured  from  a  different  view  point  and 
there  is  a  most  decided  difference  in  each  print  which  has  resulted  in 
the  three-dimensional  aspect  of  a  view.  This  point  is  mentioned  to 
prevent  arbitrary  cropping  of  finished  prints. 







>    3 

o3      *o 

§   I 




A.  L.  LUGN,  Ph.  D.  CHAPTER  13 

Every  amateur  photographer  has  at  one  time  or  another  come 
upon  landscape  scenes,  interesting  architectural  settings,  interiors  of 
large  buildings,  groups  of  people  and  no  doubt  many  other  interesting 
photographic  subjects  which  are  beyond  the  limitations  of  the  ordinary 
hand  camera.  Keen  disappointment  may  have  been  experienced  in 
an  attempt  to  photograph  these  subjects  from  a  distance  sufficient  to 
include  the  entire  horizontal  length  of  the  scene  within  the  long 
dimension  of  the  average  hand  camera  negative  by  use  of  the  short- 
focus  lens.  When  such  a  long  picture  is  finished,  the  landscape  is 
stretched  across  the  print  in  a  thin  line  with  approximately  ninety 
per  cent  of  the  print  area  a  total  waste.  The  details,  also,  are  com- 
pletely lost  in  their  minuteness.  At  one  time  or  another,  every  amateur 
has  probably  wished  for  a  panorama  camera  which  would  combine  the 
expanse  of  the  view  with  the  details  of  the  scene. 

The  Leica  camera,  with  its  large  negative  capacity  and  its  ability 
to  take  pictures  in  rapid  succession  has  brought  panorama  photography 
within  easy  reach  of  the  novice.  Chance  and  guess  work  have  been 
eliminated  from  the  operation  by  the  simplicity  and  dependability  of 
the  accessories  required.  Weighing  but  a  few  ounces,  they  consist  of 
the  following  units : 

1.  A  Ball  Jointed  Tripod  Head — for  leveling  of  the  camera  and  for 
locking  it  in  that  position. 

2.  Special  Angle  Bracket — required  for  centering  the  lens  over  the 
pivotal  point  and  for  using  the  camera  vertically. 

3.  A  Spirit  Level — fitting  into  the  clip  of  the  camera  for  horizontal 
pictures,  or  the  clip  of  the  Angle  Bracket  for  vertical  pictures. 

4.  Cable  Release — serving  to  avoid  jarring  of  camera  and  disturbing 
its  position. 

5.  Panorama  Tripod  Head— with  any  of  the  interchangeable  gradu- 
ated rings,  depending  on  lens  used.    Each  of  these  rings  has  two 
sets  of  'graduations :  one  for  horizontal,  the  other  for  vertical  use 
of  the  camera. 


Fig.  373     Accessories  for  Panorama  Photography: 

Ball  Jointed  Tripod  Head,    Spirit  Level,   Angle  Bracket  and   Panorama   Tripod   Head   with 
interchangeable  graduated  rings  for  various  lenses 

6.    Universal  View  Finder — if  any  but  the  50mm  lens  is  used. 

Obviously,  a  good  rigid  tripod  is  essential  for  this  work  in  order  to 
permit  the  camera  to  be  rotated  around  a  pivotal  point,  for  taking  sec- 
tion views  of  a  complete  circle  or  of  any  portion  of  it. 

Composing  the  Panorama 

Photographs  belong  to  two  general  classes:  those  intended  as 
records  of  objects  or  incidents,  and  those  whose  purpose  is  to  render  a 
pictorial  interpretation  of  things,  people  and  incidents.  Panorama 
photographs  usually  belong  to  the  first  classification,  but  they  may, 
if  desired,  be  used  pictorially.  Photomurals,  for  instance,  frequently 
present  opportunities  of  a  strictly  pictorial  nature  for  panorama  views. 

In  the  case  of  record  photographs,  pictorial  composition  is  not 
important  and,  therefore,  a  symmetrical  picture  is  probably  the 
simplest  and  most  satisfactory.  If  a  pictorial  panorama  is  desired,  the 
same  principles  of  good  design  and  composition  which  are  employed  in 
other  forms  of  photography  must  apply.  The  chief  difficulty  will  be 
found  in  maintaining  unity.  In  a  picture  several  times  as  wide  as  it 
is  high,  the  eye  covers  too  great  space  in  one  direction  and  is  likely 
to  fix  upon  many  irrelevant  details  without  being  led  to  any  particular 
center  of  interest.  To  avoid  this  and  to  permit  the  eye  to  travel 
smoothly  from  one  end  of  the  picture  to  another,  the  position  from 
which  the  picture  is  taken  should  be  carefully  chosen. 

Unimportant  and  undesirable  details  tending  to  distract  from  the 
main  interest  of  the  picture  should  be  carefully  eliminated.  Where 
this  is  impossible,  undesirable  details  may  be  dispensed  with  by  means 
of  paper  negatives,  enlarged  negatives,  obtained  by  reversal  and  such 
other  means  of  control  as  are  available  for  other  photographic  ren- 
dering. The  most  pleasing  panoramas  are  those  which  do  not  cover 



too  great  an-  are  of  the  circle,  preferably  no  more  than  can  be  viewed 
from  one  position  without  turning  the  head. 

Panorama  Tricks 

Certain  kinds  of  tricks  or  stunts,  possible  with  the  Leica  and 
panorama  accessories,  will  readily  suggest  themselves  to  the  reader. 
One  or  more  persons  or  objects  may  be  repeated  several  times  in  a 
panorama  with  a  continuous  background.  Other  effects  may  be  ac- 
complished with  the  camera  attached  to  a  universal  tilting  tripod  head, 
by  means  of  the  angle  bracket,  in  either  horizontal  or  vertical  posi- 
tion, making  it  possible  to  panoram  vertically  or  at  an  angle.  A  tall 
tower  or  the  details  of  a  tall  building  may  be  photographed  by 
panoraming  at  an  angle,  starting  at  the  lower  left  and  moving  upward 
to  the  right.  Interesting  panoramas  of  tall  buildings  may  be  made  in 
this  way.  This  type  of  shot  is  best  adapted  to  city  scenes  and  should 
be  very  useful  in  some  kinds  of  news  or  advertising  illustrations.  In 
making  vertical  panoramas  of  tall  buildings,  photographing  them 
from  anywhere  but  street  level  should  be  avoided  as  it  will  result  in 
"bellying  out"  of  the  portion  of  the  building  nearest  the  camera  level. 

Fig.  174     Complete  Panorama  Out- 
fit Assembled  for  Horizontal  Pic-     Fig.  175    Complete  Panorama  Out- 
tures  fit  Assembled  for  Vertical  Pictures 


me  pictures 

The  nature  of  the  subject,  its  size  and  relation  to  position  of 
camera  should  determine  the  choice  of  the  lens  used.  The  short  focus 
lenses,  such  as  the  35mm  or  50mm  are  best  adapted  to  work  in  interiors 
where  sufficient  room  for  backing  the  camera  is  not  available.  The 
longer  focus  lenses  may  be  used  for  distant  outdoor  scenes  where  it  is 
necessary  to  reach  out  for  details  of  mountain  ranges,  forests,  gla- 
ciers, etc. 

To  take  a  series  of  negatives  for  panorama  pictures,  the  first  thing 
necessary  is  to  select  a  suitable  position  for  the  camera.  This  will  be 
determined  by  the  nature  of  the  subject,  the  purpose  of  the  picture, 
available  space,  and  composition  desired,  as  outlined  in  previous  para- 
graphs. The  camera  is  set  up  on  a  sturdy  tripod,  attached  by  means 
of  the  panorama  head  and  held  either  in  the  vertical  or  horizontal 
position.  The  former  is  to  be  preferred  since  it  yields  a  higher  picture 
with  a  somewhat  better  proportioned  finished  job.  The  camera  should 
be  perfectly  level.  If  it  is  not,  the  sections,  when  trimmed,  will  bow 
up  or  down  at  the  ends,  resulting  in  a  certain  amount  of  distortion 
when  cut  to  a  rectangular  shape. 

The  next  step  is  to  determine  the  farthest  and  the  nearest  points 
in  the  picture  which  are  to  be  in  sharp  focus.  To  re-focus  between  the 
pictures  of  a  panorama  is  impractical  since  this  alters  the  relative  size 
of  the  pictures  and  they  win  not  match  up.  The  lens  stop,  therefore, 
must  be  adjusted  for  the  necessary  depth  of  focus  before  the  first  pic- 
ture is  taken.  The  depth  of  focus  scale  (on  every  Leica  lens)  should  be 
utilized  for  this.  The  finished  panorama  is  a  series  of  separate 
prints,  joined  so  as  to  look  like  one  large  print.  The  negatives 
therefore  should  be  absolutely  uniform.  In  order  to  obtain  such  nega- 
tives, a  dependable  exposure-meter  should  be  used  and  consulted  before 
each  separate  exposure.  It  is  important,  too,  that  all  exposures  in- 
tended for  one  panorama  be  taken  on  the  same  roll  of  film  to  assure 
identical  treatment  in  processing.  Make  sure  that  sufficient  film  is  in 
the  camera  before  starting  to  take  a  panorama;  reloading  the  camera 
during  a  series  of  shots  will  most  assuredly  upset  the  job.  After  the 
exposures  are  made,  the  film  should  be  processed  and  handled  through- 
out in  the  same  manner  in  which  it  would  be  handled  for  any  other 
Leica  photographic  work. 

At  times  uniform  negatives  cannot  be  obtained.  Such  may  be  the 
ease  in  a  large  interior  illuminated  with  artificial  light.  In  such  cases, 
the  differences  must  be  compensated  for  in  the  making  of  prints. 



Making  the  Print 

The  technique  of  making  prints  for  a  panorama  picture  is  not 
much  different  from  that  employed  in  making  enlargements  generally. 
The  points  of  difference  are :  1.  Once  the  size  of  the  final  print  has  been 
decided  upon  and  the  enlarger  set  and  focused,  the  latter  should  not 
be  changed  in  any  way  until  the  last  print  of  the  series  is  made. 
2.  Areas  of  prints  adjoining  each  other  must  match  in  tone  values. 
This  is  achieved  by  maintaining  a  uniform  temperature  of  developer 
throughout,  using  paper  from  the  same  package,  giving  the  same  ex- 
posure and  development  time,  if  the  negatives  are  of  uniform  density. 
If  they  are  not,  it  may  be  necessary  to  vary  the  exposures  according 
to  results  obtained  by  means  of  test  strips.  A  certain  amount  of 
dodging  or  shading — holding  back  or  printing  in,  may  be  required  for 
best  results.  It  is  advisable  to  make  several  prints  of  each  section  and 
to  match  the  best  ones  for  assembling  the  finished  picture. 

Assembling  and  Mounting  the  Finished  Panorama 

After  the  prints  are  made,  they  must  next  be  matched,  trimmed, 
and  mounted.  A  suitable  cardboard  should  be  selected  according  to  tEe 
photographer's  tastes  and  desires,  just  as  in  mounting  any  other  kind 
of  print.  Paste  or  dry  mounting  tissue  may  be  used,  but  the  writer 
has  found  dry  mounting  tissue  to  be  the  more  satisfactory.  Paste 
causes  the  prints  to  expand,  not  always  uniformly,  and  they  contract 
on  drying.  This  almost  invariably  results  in  the  prints  pulling  apart 
slightly,  leaving  a  small  but  undesirable  crack  between  the  sections. 
This  may  be  avoided  with  dry  mounting  tissue,  and  with  careful 
manipulation,  perfectly  printed  sections  may  be  joined  with  scarcely 
a  line  showing.  However,  the  most  carefully  mounted  prints  some- 
times pull  slightly  apart  in  damp  weather  due  to  the  expansion  of  the 
mounting  board. 

Since  the  trimmed  edge  of  the  paper  is  white,  it  is  advisable  to 
darken  the  edges  with  a  pencil  where  dark  areas  of  adjoining  prints 
meet.  If  white  or  light-colored  board  is  used  for  mounts,  it  should 
also  be  shaded  with  the  pencil  to  match  the  print  along  all  lines  where 
prints  meet.  This  is  a  small,  but  not  unimportant,  detail. 

A  sheet  of  dry  mounting  tissue  is  tacked  to  the  back  of  every 
selected  untrimmed  print  of  the  panorama.  The  overlap  at  the  sides 
of  each  sectional  print  is  carefully  trimmed  either  on  a  sharp  and  truly 
square  trimming  board,  or  by  means  of  a  straight-edge  and  a  knife  or 
razor  blade.  When  this  is  completed  the  details  of  adjoining  sections 
are  made  to  match.  The  prints  are  then  placed  on  the  table  matched, 
ready  to  be  put  together.  An  accurate  outline  of  the  finished  print  is 


then  drawn  lightly  with  pencil  on  the  mount,  squaring  it  up,  if  neces- 
sary with  a  straight  edge  or  a  T  square.  Each  sectional  print  is  fitted 
into  its  position  on  the  mount,  top  and  bottom  receiving  the  final  trim. 
They  are  then  ready  to  be  mounted. 

A  pencil  mark  is  made  lightly  on  every  sectional  print  and  on  the 
mount,  indicating  its  final  position  on  same.  The  edges  of  each  print 
should  be  shaded  with  pencil  at  this  point  as  well  as  the  mount  proper 
at  points  where  two  prints  join.  It  is  best  to  begin  dry  mounting  the 
print  by  starting  with  the  center  section.  The  sections  should  be 
placed  on  the  mount  one  at  a  time,  lightly  tacked  with  a  tacking  iron 
to  the  mount  and  then  placed  into  the  dry  mounting  press  for  about 
15  to  30  seconds.  If  this  is  done  carefully,  no  overlapping  will  take 
place.  It  is  possible  to  use  an  electric  iron  for  dry  mounting,  but  the 
manipulation  must  be  deft  to  avoid  scorching  and  marks. 

For  permanence,  and  because  of  the  amount  of  care  and  work 
involved  in  the  making  of  such  a  print,  it  is  best  to  frame  it  under 
glass  on  completion.  If  matt  or  semi-matt  paper  is  used  for  the  finished 
print,  satisfactory  preservation  may  be  obtained  by  spraying  the  fin- 
ished print  and  the  entire  mount  with  one  or  two  coats  of  clear  lacquer, 
which  will  protect  it  against  dust  and  dirt.  Thus  protected,  the  print 
may  be  washed  with  a  damp  cloth  if  a  good  grade  of  lacquer  has  been 

There  are  other  ways  of  mounting  prints,  rubber  cement  or 
vegetable  paste  being  quite  as  efficient,  and  frequently  more  con- 
venient. Not  many  amateurs  own  a  dry  mounting  press,  and  they 
may  prefer  these  other  methods,  which  are  described  elsewhere  in  this 
volume.  (See  chapter  on  Photomurals  for  mounting  with  vegetable 
paste,  and  chapter  on  Enlarging  and  Printing  for  mounting  with, 
rubber  cement.) 

Fig1.  176  Hall  of  Elephants — Nebraska  State  Museum — A  Panorama  Leica 
Picture  Made  by  Dr.  A.  L.  Lugn 

How  the  picture  was  made...  50mm  f:3.5  Elmar  lens  with  diaphragm  set  at  f:12.5,  2  min- 
ute exposures,  DuPont  Superior  Film.  Seven  separate  negatives  used  to  make  the  complete 
panorama  view. 




A  few  months  ago  the  Eastman  Kodak  Company  placed  at  the 
disposal  of  Leiea  workers  a  new  medium  for  direct  Color  Photography 
which  eclipses  most  existing  standards  and  results  achievable  hereto- 
fore in  this  exciting  field.  Luckily  for  Leiea  workers,  the  original 
designer  of  their  camera  selected  the  35mm  film  for  its  negative 
material,  and  the  new  film  is  available  at  present  in  this  size  only. 
The  new  medium — KODACHROME  FILM — was  offered  to  Leiea  users 
after  having  been  successfully  used  for  over  fifteen  months  in  the 
field  of  16mm  cinephotography.  Vast  improvements  made  in  the 
material  proper,  as  well  as  in  its  processing,  resulted  in  a  film  which 
leaves  little  more  to  be  desired  of  it  as  far  as  emulsion  speed,  color 
rendering  qualities  and  general  flexibility  are  concerned. 

As  matters  stand  now,  it  is  extremely  simple  to  obtain  one  or  a  num- 
ber of  natural  color  transparencies;  in  fact,  almost  less  difficult  than  to 
produce  a  good  black  and  white  negative.  While  subsequent  production 
of  color  prints  on  paper  is  somewhat  more  complicated,  it  is  nevertheless 
quite  feasible  through  one  of  the  two  methods: 



By  far  the  simplest  part  of  Natural  Color  Photography  is  the  making 
of  color  transparencies  on  Kodachrome  film.  Available  in  daylight  loading 
magazines,  ready  to  be  inserted  into  the  camera,  in  lengths  sufficient  for 
18  exposures,  Kodachrome  need  only  be  exposed  correctly,  sent  to  Eastman 
for  processing  (the  cost  of  which  is  included  in  the  original  price  of  the 
roll),  and  it  is  returned  in  the  form  of  excellent  positive  transparencies — 
sharp,  grainless,  free  from  color  fringes,  patterns  or  screens  (shortcom- 
ings of  some  of  the  other  color  materials). 

Kodachrome  Film 

Based  upon  the  subtractive  principle  of  color  photography,  Kodachrome 
reproduces  natural  colors  as  faithfully  as  seems  possible  at  present.  The 
separation  of  colors  is  secured  in  an  unusual  but  extremely  efficient  man- 
ner: within  the  body  of  the  emulsion  itself.  This  is  accomplished  by  coat- 
ing the  film  support  five  times.  These  five  layers  consist  of  three  coats  of 
color  sensitive  emulsions,  which  are  separated  by  two  coats  of  plain  gelatine. 


Each  of  the  three  coatings  of  emulsion  is  selectively  sensitized:  that  adjoin- 
ing the  film  support  is  red  sensitive;  the  center  coating  is  green  sensitive; 
and  the  outer,  top,  coat  is  sensitive  to  blue-violet.  The  two  layers  of  plain 
gelatine  prevent  the  sensitizers  of  emulsions  from  straying  away  from 
their  respective  coatings.  The  all-over  thickness  of  these  five  layers  is  no 
more  than  that  of  the  emulsion  of  ordinary  black  and  white  negative 

When  an  image  is  focused  upon  Kodachrome  film,  some  part  of  the 
picture  is  formed  in  each  of  these  three  layers,  depending  upon  the  color 
of  the  subject:  red  colored  objects  in  the  picture  are  recorded  by  the  bot- 
tom, red-sensitive  layer;  green  colored  objects  by  the  center,  green-sensi- 
tive layer;  and  blue  colored  objects  by  the  top,  blue-violet  sensitive  layer. 
After  the  film  is  processed  by  the  reversal  method,  each  of  the  three  coats 
of  selectively  sensitized  emulsions  is  dyed  with  color  complementary  to  its 
original  sensitivity.  The  bottom,  red-sensitive  emulsion  is  dyed  blue- 
green.  The  center,  green- sensitive  coat  is  dyed  red  (magenta).  And  the 
top,  or  blue-violet  sensitive  layer  is  dyed  yellow. 

During  the  processing  the  metallic  silver  image  is  dissolved  and  thus 
removed,  leaving  a  pure  dye  image  reproducing  beautifully  all  colors  of 
the  original. 

Two  Types  of  Kodachrome 

Because  each  of  the  three  coatings  of  emulsion  can  be  sensitized  select- 
ively, Kodachrome  Film  can  be  made  for  practically  any  purpose  and  of 
varying  degrees  of  sensitivity  in  any  of  the  spectral  color  regions.  Accord- 
ingly, two  types  of  Kodachrome  Film  are  available  to  suit  the  two  kinds 
of  illumination:  daylight  and  artificial  light. 

The  Kodachrome  Regular  (K135)  has  an  emulsion  which  is  designed 
to  produce  correct  color  rendering  in  daylight  without  any  filters  or  other 
accessories.  However,  a  special  Haze  Filter  will  improve  the  results  if 
used  under  certain  conditions.  Ultra-violet  light  which  may  occur  in 
extremely  distant  scenes,  snow  scenes  and  at  high  altitudes,  will  record 
on  the  Kodachrome  Film  as  violet.  To  correct  this,  the  Kodachrome  Haze 
Filter  should  be  used  (it  requires  no  change  in  exposure).  The  same 
filter  will  also  improve  color  rendering  by  imparting  more  warmth  to  the 
tones  of  scenes  and  people  photographed  on  a  gray  day  or  in  the  shade. 

Kodachrome  Regular  can  be  used  in  artificial  light,  provided  a  Koda- 
chrome Filter  for  Photoflood  (blue)  is  placed  in  front  of  the  lens.  This 
filter  changes  the  quality  of  artificial  light  to  that  of  daylight  by  reducing 
the  excess  of  red  prevailing  in  artificial  light.  There  being  a  special  type 
of  film  available  for  artificial  light,  the  use  of  the  Regular  film  should  be 
restricted  to  daylight  work.  The  filter  generally  has  an  exposure  factor 
of  4x,  which  calls  for  too  long  exposures. 

The  Kodachrome  Film  Type  A  (K135A)  has  an  emulsion  especially 
corrected  for  use  with  artificial  illumination  so  that  no  filter  whatever  is 
needed  to  obtain  correct  color  rendering.  Specifically,  the  color  sensitivity 
of  this  film  is  very  accurately  adjusted  for  light  of  Photoflood  and 
Photoflash  bulbs.  No  other  bulbs  should  be  used  if  correct  color  rendering 
is  desired.  High-wattage  tungsten  bulbs  are  apt  to  make  the  pictures  too 
red.  The  "daylight"  or  blue  bulbs  should  not  be  used  because  they  will 
make  the  pictures  too  blue.  Similarly,  arc  lamps  that  produce  light 


Color  Photography 

approaching-  daylight  in  quality  will  make  the  pictures  too  blue  on  Type  A 
Film.  Primarily  intended  for  work  in  artificial  light,  the  Type  A  Film 
is  not  recommended  for  daylight,  for  which  purpose  it  can,  however,  be 
used  in  connection  with  the  special  Type  A  Kodachrome  Filter  for  Daylight, 
which  is  reddish-yellow  to  change  the  quality  of  daylight  to  artificial  light 
by  reducing  the  ultra-violet  and  the  blue  portion  of  its  light. 


Every  roll  of  Kodachrome  Film  is  accompanied  by  very  specific  recommendations  for 
exposures.  The  most  satisfactory  results  will  be  secured  by  following  these  instructions  to 
the  letter.  Color  photography  requires  much  more  critically  correct  exposures  than  black- 
and-white  work.  Generally  the  latitude  of  color  film  is  much  more  limited  than  that  of 
black-and-white  films  (about  1/3).  Such  variables  as  climatic  conditions,  to  which  Koda- 
chrome Film  is  rather  sensitive,  geographical  latitude,  accuracy  of  shutter  speed  and  lens 
diaphragm,  may  tend  to  produce  some  over  or  under  exposures.  Until  all  such  variables 
are  fully  under  control  it  may  be  best  to  take  three  pictures  of  each  scene:  one  exposure 
following  the  manufacturer's  recommendation,  one  at  twice,  and  one  at  half  the  recom- 
mended exposure.  Intelligent  and  judicious  use  of  a  good  exposure  meter  of  the  photo- 
electric variety  should  prove  very  valuable  for  getting  consistently  good  results  with 
Kodachrome  Film.  However,  due  to  variations  in  color  sensitivity  of  various  meters, 
even  those  of  the  same  make,  they  should  be  carefully  checked  and  calibrated  against 
actual  results.  The  best  way  to  calibrate  one's  meter  is  to  make  a  few  exposures  strictly 
in  accordance  with  manufacturer's  recommendations,  while  at  the  same  time  securing 
a  reading  with  one's  own  exposure  meter.  If  both  indications  coincide  and  the  resulting 
pictures  are  right  the  meter  is  correctly  calibrated.  Slight  differences  can  be  adjusted 
by  resetting  the  emulsion  speed  from  that  recommended  by  the  exposure  meter  to  that 
corresponding  to  exposure  setting  which  secured  a  well  exposed  picture. 

For  general  guidance,  subject  to  variations,  it  may  be  said  that  the  Kodachrome  Films 
can  be  rated  as  follows : 

KODACHROME   FILM:  Weston  Scheiner  Din 

Regular    K135     (daylight)     8                     18°  11/10 

(Photoflood    light)*     3                      14°  7/10 

Type  A.   K135A    (Photoflood  light)    12                     20°  13/10 

(daylight)  f      8                     18°  11/10 

*  with   the    Kodachrome    Filter   for    Photoflood. 

f  with  the  Type  A   Kodachrome  Filter  for  Daylight. 


Color  photography  has  its  own  requirements  of  illumination  which  are  quite  different 
from  those  applying  to  black  and  white  work.  In  the  latter,  the  differentiation  of  form, 
lines  and  planes  is  produced  by  contrasts  of  brightness  and  shadows  cast.  In  color  woric 
much  less  contrasty  illumination  is  required  because  the  "tones"  and  gradation  are  pro- 
duced by  color.  In  outdoor  work  best  results  are  obtained  with  the  sun  approximately 
behind  the  camera.  It  should  be  remembered  that  increased  exposures  are  required  if  the 
sun  is  to  one  side  of  the  camera,  (almost  double),  and  still  longer  exposures  when  the 
camera  is  facing  the  sun  (about  four  times  normal). 

For  indoor  work  with  Photofloods  a  flat  "flood"  type  illumination  should  be  provided 
to  avoid  shadows  as  much  as  possible.  Assuming  that  lights  are  being  placed  on  both 
sides  of  the  camera,  most  pleasing  results  will  be  secured  when  some  60%  of  the  entire 
amount  of  light  will  come  from  one  side,  while  about  40%  from  the  other. 

Several  points  should  be  remembered  when  arranging  lights  for  indoor  color  photog- 
raphy. All  Photofloods  should  be  new.  Each  bulb  should  be  used  in  a  suitable  reflector, 
the  Kodafleetor  type  or  the  Kodak  Handy  Reflector  providing  the  least  expensive  and  most 
efficient  form.  Each  reflector  should  be  directed  upon  the  subject  so  that  the  full  amount 
of  light  reaches  it.  When  working  in  artificial  light,  daylight  should  be  completely  ex- 
cluded ;  otherwise  the  pictures  will  show  too  much  blue  in  those  portions  which  were 
illuminated  by  daylight. 

Instructions  accompanying  each  roll  of  film  contain  a  complete  exposure  table  for  use 
with  Photoflash  bulbs,  which  when  followed  to  the  letter  with  the  aid  of  a  tape  measure 
will  assure  perfect  results,  where  the  use  of  Photoflashes  is  preferred  to  Photofloods,  as 
in  action  shots,  photography  of  children,  pets,  etc. 


Viewing  and  Projection 

Though  a  few  photographers  bemoan  it,  it  seems  particularly  fortunate  that  the  pro- 
cessing of  Kodaehrome  Film  is  attended  to  by  The  Eastman  Kodak  Company.  It  must  be 
remembered  that  the  film  consists  of  reversed  images,  there  being:  no  negative.  Subsequent 
manipulations  called  for  in  the  making  of  color  enlargements  require  absolutely  perfect 
transparencies,  free  from  scratches,  blemishes  and  any  traces  of  handling.  The  Kodachrome 
transparencies  as  they  arrive  from  the  processing  laboratory  are  very  carefully  packed  and 
as  a  rule  reach  us  in  excellent  condition.  They  should  be  immediately  and  permanently 
protected  against  any  possible  damage  which  may  result  if  they  are  put  in  an  enlarger, 
projector,  or  Stero  Viewer.  Depending  upon  the  use  to  which  they  are  put,  they  should 
be  suitably  mounted  between  glass.  A  number  of  mounts,  masks  and  mats  are  available 
to  meet  adequately  any  possible  requirements.  The  Kodachrome  35mm.  transparencies  can 
be  mounted  either  in  standard  lantern  slides  (3*4"  x  4")  or  Leica  size  lantern  slides 
(2"  x  2")  or  into  strips  of  three  exposures  each  for  Stereo  Viewing  (bound  between  special 
cover  glass  measuring  35  x  120  mm,  available  through  E.  Leitz,  Inc.,  New  York).  In 
addition  to  masks  required  for  mounting  between  glass  there  are  hand-viewing  mats  avail- 
able in  horizontal  or  vertical  arrangement. 

Under  no  circumstances  should  Kodachrome  transparency  strips  be  used  directly  in 
projectors  or  enlargers  because  scratches  and  abrasive  marks,  impossible  to  prevent,  will 
promptly  ruin  the  usefulness  of  the  valuable  strip.  At  the  moment  of  writing  no  color 
duplicates  are  possible.  Black  and  white  copies  can  be  made  on  panchromatic  negative 
material  by  contact  printing.  From  such  duplicate  negatives  subsequent  black  and  white 
enlargements  can  easily  be  made. 

Black  and  White  Enlargements  From  Kodachrome 

Black  and  white  enlargements  from  Kodachrome  transparencies  can  easily  be 
secured  by  projection  upon  Eastman  Kodak  Direct  Positive  paper.  This  is  a  reversible 
material,  very  easy  to  handle  and  its  only  drawback  is  that  the  Direct  Positive  paper  is 
somewhat  slower  than  the  usual  projection  papers.  One  can  secure  an  inexpensive  com- 
plete outfit  for  direct  positive  work  either  for  sepia  effects  or  for  black  and  white  effects 
by  ordering  same  through  any  Kodak  dealer.  Enlargements  up  to  5  x  7  can  easily  be  made 
but  if  8  x  10  enlargements  are  wanted  a  photoflood  bulb  should  be  used  in  the  enlarger. 
One  should  be  tempted  to  make  black  and  white  enlargements  from  Kodachrome  trans- 
parencies for  they  are  free  from  grain  and  have  excellent  definition. 

It  should  be  remembered  when  making  enlargements  upon  direct  positive  paper  that 
the  Kodachrome  film  must  be  placed  in  the  enlarger  with  the  emulsion  away  from  the 
lens  to  assure  that  the  image  will  not  come  out  reversed  from  right  to  left. 

The  greatest  enjoyment  can  be  derived  from  natural  color  transparencies  by  viewing 
them  in  the  form  of  brilliantly  projected  pictures.  There  is,  however,  a  keen  desire  on  the 
part  of  photographers  to  make  color  prints,  a  desire  which  can  now  be  gratified.  The 
making  of  prints  from  Kodaehrome  transparencies  resolves  itself  into  two  main  parts. 

Three  Color  Separation  Negatives 

The  most  critical  and  difficult  part  of  the  procedure  is  the  production 
of  three  negatives  from  the  Kodachrome  positive  transparency,  in  such 
a  manner  that  each  of  these  negatives  records  details  of  one  of  the  three 
basic  colors  as  they  were  separated  originally  within  the  body  of  the 
emulsion  of  the  Kodachrome  Film.  This  is  accomplished  by  projecting 
fche  Kodachrome  positive  transparency  by  means  of  an  enlarger  upon 
panchromatic  negative  material,  first  through  a  green  filter,  then  through 
a  red  filter,  and  finally  through  a  blue  filter.  These  negatives  are  made 
by  three  separate  exposures  upon  three  separate  panchromatic  negatives 
of  any  desired  size.  The  filters  required  for  this  are  of  the  standard 
three-color  separation  filter  set  consisting  of  A  filter  (25)  B  filter  (58)  and 
C-5  filter  (47). 

The  respective  densities  of  these  three  negatives  will  have  to  be  such  as  to  produce 
good  color  balance  later  in  the  making  of  the  paper  print.  To  secure  this  balance  two 
conditions  should  be  met.  The  enlarger  lens  should  be  exceptionally  well  corrected  for 
color.  A  Photoflood  bulb  should  be  used  in  the  enlarger,  or  a  blue  filter  (daylight) 


Color  Photography 

should  be  placed  between  the  bulb  and  the  lens  of  the  enlarger.  The  exposure  factors 
of  the  three  filters  used  should  be  definitely  established  with  regard  to  both  light  source 
of  the  enlarger  and  film  used  before  exposures  are  made.  Thus,  for  instance,  if  a  film 
as  Eastman  Kodak  Panatomic  is  used  for  making  the  negatives,  the  respective  filter 
factors  will  be  as  follows:  A  Filter — 3,  B  Filter — 8,  and  C-5  Filter— 12,  if  tungsten  light 
is  used.  For  other  films,  filter  factors  referring  to  artificial  light  offered  on  page  95 
should  be  consulted,  or  obtained  direct  from  the  manufacturer  whose  film  is  used. 

It  should  be  remembered  that  the  original  Kodachrome  transparency  should  be 
placed  in  the  enlarger  with  the  emulsion  side  facing  away  from  the  enlarger  lens.  This 
will  assure  correct  placement  of  subject  on  finished  color  prints. 

The  negatives  are  then  developed  according  to  recommendations  of  the  manufacturer 
to  secure  full  detail  and  gradation.  Each  negative  is  carefully  identified  by  a  proper 
mark  referring  to  the  filter  it  was  made  with.  The  negative  made  through  the  red  filter 
will  then  become  the  blue  printer ;  that  made  through  the  green  filter,  the  red  printer ;  and 
the  one  made  through  the  blue  filter,  the  yellow  printer. 

Making  Separation  Negatives  in  the  Camera 

The    Kodachrome   film    is    undoubtedly    the    quickest    and    simplest    method    of    obtaining 
the    original    color    positive.     Requiring    no    accessories    "in    the    field"    it    can    be    broadly 
applied  to  action   photography,   and  photography   of  living  and   moving   objects.      At  times, 
however    it    may    be    desirable    and    possible    to    make    three 
separate    negatives    of   the   same   object.     This    is    done    sim- 
ply by  making  three  exposures    on   the   same   Panchromatic 
film,    one   exposure   through   each    of   the   standard   "Wratten 
three    color    separation    filters    A,    B    and    C-5.      A    set    ol 
these   three   filters    mounted    in    a    rotating    segment   is    pro- 
duced   and    distributed    by    the    Chess    United    Co.    of    New 
York.     This  combination  set  is  known  as  the  "Trichromatic 
Separation     Filter,"     is     mounted     directly     over     the     lens 
and    each    of    its    three   filters    moved    into    taking    position        Trichromatic  Separation 
as    required.       (The    same    filter    can    also    be    used   in    con-        Filter  for  use  on  Cam- 
nection    with    making    three    color    separation    negatives    by         era   or   Enlarger   Lens. 
projection    in    the    enlarger.) 

The  exposure  factors  of  the  three  color  separation  filters  vary  depending  on  the  nega- 
tive material  used.  They  will  be  found  in  the  filter  factor  table  on  page  95.  As  a  matter 
of  convenience  the  following  filter  factors  for  DuPont  Superior  Film  are  given : 

Daylight      Photoflood  Mazda 

A    95  4 

B     5  6  6 

C-5 6  10  13 

It  seems  almost  superfluous  to  point  out  that  the  camera  must  be  rigidly  supported 
for  the  making  of  three  color  separation  negatives.  A  neutral  density  scale  consisting  of 
step  gradations  of  white,  grey  and  black,  sharply  outlined,  should  always  be  placed  in  a 
corner  of  the  picture  (so  as  not  to  appear  later  in  the  finished  print  but  to  appear  on 
every  negative).  The  scale  must  be  illuminated  in  the  same  manner  as  the  subject  and 
should  be  sharply  in  focus  to  serve  not  only  as  a  means  of  comparing  the  density  of  the 
negative  but  also  as  a  means  for  registering  the  three  prints  in  superimposing  them. 
When  the  negatives  are  developed  and  dried  they  should  be  marked  along  the  edge  with 
good  water  proof  India  ink  as  follows:  B  for  the  negative  taken  through  Red  filter  for 
blue  color ;  R  for  the  negative  taken  through  green  (to  be  colored  red)  ;  Y  for  the  negative 
taken  through  blue  filter  (to  be  colored  yellow) . 

The  color  balance  of  the  final  prints  will  depend  upon  the  care  and  relative  correct- 
ness of  exposure  used  in  making  the  original  black  and  white  negative  in  the  camera,  or 
of  the  separations  made  from  the  Kodachrome  positive.  If  correct  exposure  has  been 
given  the  neutral  density  scale  lef erred  to  will  have  the  identical  tone  value  in  each 
negative.  If  the  original  negatives  are  not  correctly  exposed,  it  may  some  times  be  pos- 
sible to  make  a  slight  compensation  by  varying  the  exposure  during  subsequent  manipula- 
tions, but  the  results  will  not  be  as  satisfactory  as  those  originating  from  correctly  bal- 
anced negatives. 

The  problem  of  securing  proper  balance  of  densities  in  the  three-color 
separation  negatives   requires   considerable   experience  before   satisfactory 


results  are  obtained  and  a  good  deal  of  experimental  work  will  have  to 
be  done  before  the  proper  technique  is  acquired.  However,  once  a  set  of 
satisfactory  three-color 'separation  negatives  is  available,  one  may  proceed 
to  make  color  prints  by  either  of  the  two  methods  outlined  below. 

Defender  Chromatone  Process 

For  Natural  Color  Photographic  Prints 

All  manipulations  involved  in  the  Defender  Chromatone  Process  are 
very  simple,  and  little  difficulty  should  be  experienced  by  the  Leica  worker 
who  is  already  familiar  with  the  developing  and  toning  technique.  The 
process  is  based  upon  the  principles  of  three-color  photography  of  the 
subtractive  type.  Briefly,  the  process  involves  the  superimposition  of 
three  transparent  positive  prints:  one  dyed  yellow,  another  magenta,  and 
the  third  blue-green — all  mounted  upon  a  white  background,  the  finished 
product  resulting  in  a  picture  in  natural  colors.  The  original  photograph 
may  be  taken  either  by  direct  color  film,  such  as  Kodachrome  or  three 
separate  negatives  can  be  made  by  direct  photography  through  green,  red 
and  blue  filters.  When  the  original  color  photograph  has  been  made  on 
Kodachrome,  it  will  be  necessary  to  make  three  color  separation  negatives 
as  described  above  from  which  subsequently  Chromatone  color  positives  are 

White  light  is  a  mixture  of  all  known  colors.  White  is  not  an  absence 
of  color,  but  on  the  contrary  it  is  the  sum  total  resulting:  from  the 
presence  of  all  colors.  To  show  the  presence  of  the  components  of  light  we 
can  pass  a  beam  of  this  white  light  through  a  glass  prism  with  the  result 
that  the  colors  are  separated  into  the  spectrum:  violet,  blue,  bluish-green, 
green,  yellow,  orange  and  red.  Each  of  these  spectral  colors  is  a  true 
color  which  cannot  be  broken  down  or  separated  into  other  colors  by  any 
known  methods. 

For    practical    purposes,    the    spectrum    may    be    considered    divided    as    shown    in    the 
following:  diagram: 








|         Green 



\400                        500              ^yV^            600 


^                                                       v^ 

Bluish-Green                                           Orange 

The  color  of  any  object  is  due  to  the  color  of  that  portion  of  the  incident  light  which  is 
reflected  from  its  surface.  The  other  colors  of  the  incident  light  that  are  not  reflected 
are  absorbed  by  the  object. 

It  is  commonly  known  that  any  color  can  be  reproduced  by  mixing  varying  quantities 
of  blue-violet,  green  and  red  colors.  Therefore  all  three-color  processes  are  based  on 
photographing  separately  the  primary  colors:  red,  green  and  blue.  In  the  case  of  Koda- 
ehrome  this  is  accomplished  within  the  body  of  one  composite  emulsion  while  in  three 
color  separation  negatives  made  in  the  camera,  or  by  projection,  this  is  done  by  three 
separate  exposures  made  through  red,  green  and  blue  light  filters  respectively. 


Color  Photography 

Making  the  Actual  Color  Prints 

The  principle  of  color  prints  is  based  upon  considering  the  white  paper 
stock  upon  which  the  print  is  being  built  up  as  the  light  source.  This 
white  paper  stock  reflects  all  colors  of  the  spectrum.  From  each  of 
the  three  separation  negatives  secured  either  directly  through  the  camera, 
or  by  projection  from  a  color  transparency  like  the  Kodachrome,  posi- 
tive prints  are  made  upon  a  special  stripping  film  (Chromatone  Print 
paper)  which  is  exposed  and  handled  similarly  to  projection  paper. 
The  collodion  emulsions  of  the  Chromatone  Print  Paper  are  stripped  off 
their  base,  toned  to  the  proper  color,  which  is  complementary  to  the  color 
of  the  filter  through  which  its  respective  negative  had  been  made,  and 
superimposed  over  each  other  upon  the  white  paper  backing.  The  comple- 
mentary color  of  red  is  blue-green;  it  transmits  both  blue  and  green, 
absorbing  red,  being  therefore  white  minus  red.  The  complementary  color 
of  green  is  blue  red  or  magenta;  it  transmits  both  the  blue  and  red,  and  is 
therefore  white  minus  green.  The  complementary  color  of  blue  is  red, 
green  or  yellow;  it  transmits  both  red  and  green,  and  is  white  minus  blue. 
When  all  color  prints  are  superimposed  upon  the  white  mounting  paper, 
each  print  will  thus  subtract  from  the  white  of  the  paper  all  the  portions 
of  the  original  which  were  not  blue,  green  or  red,  according  to  the  respect- 
ive light  filters  through  which  its  negatives  were  taken.  Such  superimposed 
prints  if  correctly  registered  will  give  a  print  in  natural  color. 

The  black  and  white  Chromatone  prints  are  thoroughly  fixed  and  washed  for  at  least 
15  minutes  in  running  water.  In  the  fixing  bath  the  gelatin  emulsion  can  be  stripped 
or  separated  from  the  paper  backing.  The  stripped  emulsions  should  be  handled  with 
reasonable  care  to  avoid  formation  of  kinks.  The  next  step  is  to  tone  each  film,  in  its 
respective  Chromatone  toning  solution. 

Toning  the  Separation  Positive 

The  stripped  off  black  and  white  positive  films  which  are  intended  for  the  Red  and 
Blue  images  are  placed  together  in  one  tray  and  the  Red  and  Blue  toner-A  made  up 
according  to  the  formula  sheet  accompanying  the  materials  is  poured  over.  They  should 
remain  in  the  A  solution  for  at  least  15  minutes  thoroughly  agitated  until  all  of  the  black 
silver  is  removed.  When  these  prints  are  thoroughly  toned  they  will  appear  as  a  light 
greenish  blue  image.  They  are  then  placed  in  running  water  and  thoroughly  washed 
for  about  10  minutes.  It  is  essential  that  hands  be  kept  clean  at  all  times  to  avoid  con- 
tamination of  various  solutions. 

After  this  washing,  the  film  to  be  toned  is  placed  in  the  Red  toner  B,  and  allowed 
to  tone  for  about  10  minuf-es.  The  solution  is  then  poured  off  for  use  a  second  time, 
and  the  print  is  immersed  for  three  minutes  in  a  15%  hypo  solution  (granular  or  rice 
hypo:  2%  oz.  (70  grams) — distilled  water  32  oz. —  (1000  cc.)  (Do  not  use  acid  fixing  hypo). 
It  is  then  washed  for  about  15  minutes  in  running  water. 

Similarly,  the  film  to  be  toned  Blue-green  is  placed  in  the  Blue  toner  B  and  allowed 
to  remain  for  about  10  minutes,  after  which  the  toner  is  poured  off  for  use  a  second 
time,  and  the  print  immersed  in  a  tray  of  weak  hydrochloric  acid  solution  for  about  on*1 
minute.  Use  one  part  of  diluted  solution  hydrochloric  acid  CP :  16  oz.  (500  cc.) — distilled 
water  48  oz.  (1500  cc)  with  one  part  of  water.  The  print  is  then  thoroughly  washed 
in  running  water  for  about  10  minutes  after  which  it  is  placed  in  a  tray  containing 
standard  hypo  solution  (see  above)  until  greenish  tones  have  changed  to  blue.  It  is 
then  washed  for  20  minutes  in  running  water. 

The  Yellow  toning  solution  (Yellow  Toner  A)  is  supplied  in  two  solutions,  equal 
parts  of  which  are  mixed  foi  one.  The  print  to  be  toned  yellow  is  immersed  in  this 
solution  for  about  15  minutes.  This  work  may  be  carried  on  simultaneously  with  the 
blue  and  red  toning  operations,  separate  trays  being  used.  At  the  end  of  about  15 
minutes  the  solution  is  poured  off  into  a  graduate  and  10  cc  (3  drams)  of  standard  hypo 
solution  is  added  to  every  50  cc  (2  oz. )  of  working  solution,  and  thoroughly  mixed.  Next 
wash  the  print  for  2  or  3  minutes  in  running  water,  or  in  one  complete  change  of  water, 
return  it  to  the  tray  and  pour  the  solution  back  on  the  print.  This  operation  should  be 
done  quickly,  and  the  tray  should  be  vigorously  rocked  for  about  1  minute  to  prevent 


any  streaking  of  the  yellow  image,  The  print  is  now  allowed  to  remain  in  the  solution 
for  about  3  minutes,  after  which  the  solution  is  discarded,  the  print  washed  for  a  minute 
or  two  in  clear  water,  and  then  immersed  for  about  1  minute  in  a  solution  made  up  of 
standard  hypo  solution — one  part,  water  three  parts.  Do  not  keep  the  print  longer  than 
one  minute  in  this  solution  as  the  image  at  this  stage  is  slightly  soluble  in  hypo  and 
highlight  detail  may  be  lost  thereby.  Wash  the  film  immediately  for  not  _less  than  20 
minutes  in  running  water.  The  yellow  image,  after  thorough  washing:,  is  immersed  for 
about  2  minutes  in  the  Yellow  toner  B,  and  then  washed  in  running:  water  for  -about  20 
minutes.  It  is  then  ready  for  assembling. 

The  three-color  images  are  now  registered  on  a  gelatin  coated  paper  (Chromatone 
Backing-  Paper)  which  has  been  previously  soaked  thoroughly  in  water.  Lay  the  backing: 
paper  gelatin  side  up,  on  a  clean  ferrotype  tin,  clean  glass  or  Masonite  tempered  hard 
board,  or  on  any  flat  waterproof  surface.  The  Yellow  image  is  placed  first  on  the  paper 
and  squeegeed  firmly  into  place,  emulsion  side  down,  and  allowed  to  remain  for  a  few 
minutes.  The  Red  image  is  then  placed  on  top  of  the  Yellow,  pushed  carefully  into 
register,  squeegeed  lightly,  the  register  checked,  and  adjusted  if  necessary,  and  the  Bed 
image  squeegeed  firmly  into  place.  If  at  this  point  the  two  images  do  not  appear  exactly 
in  register,  the  Red  sheet  may  be  peeled  off  carefully,  re-moistened  and  registered  again. 
It  will  be  found  easier  to  register  the  Eed  and  Yellow  images  if  they  are  viewed  through 
a  light  blue  filter. 

The  Blue  image  is  then  superimposed  upon  the  other  two,  precisely  as  described  above, 
completing  the  color  print ;  all  prints  emulsion  side  down. 

The  print  is  now  allowed  to  remain  in  the  air  for  about  10  minutes  until  the  surface 
dries  to  some  extent.  Next,  the  damp  print  should  be  trimmed  so  that  the  edges  of  the 
collodion  layers  are  flush.  It  is  then  placed  on  a  piece  of  rigid,  hard  waterproof  material. 
Masonite  Tempered  Hard  Board  is  admirably  suited  for  this  purpose. 

Ordinary  Kraft  gummed  tape  is  moistened  and  the  damp  print  fastened  to  the  board 
with  this  tape  overlapping  the  print  about  3/16"  on  all  four  edges.  Do  not  have  the 
gummed  tape  too  wet  or  the  gum  will  ooze  between  the  print  and  the  board,  making  it 
difficult  to  remove  the  print. 

The  print  will  dry  rapidly,  stretched  absolutely  fiat.  It  can  be  loosened  from  the  board 
when  dry  by  carefully  inserting  a  sharp  knife  through  the  tape  under  the  edge  of  the 
print  and  running  it  around  the  print. 

Chromatone  prints,  ordinarily  processed,  dry  with  a  high  gloss  and  great  color 
brilliancy,  which  is  considered  desirable  for  illustrative  and  commercial  work. 

A  MATT  finish  can  be  obtained  by  rubbing  over  the  glossy  surface  with  fine  dry 
pumice  powder.  If  the  finished  print  is  given  a  coat  of  good  matt  lacquer  applied  with 
an  air  brush,  varying  degrees  of  matt  finish  can  be  secured. 

To  obtain  rougher  surfaces,  any  of  the  regular  rough  textured  papers,  such  as 
Defender  Veltura  Q,  can  be  used  instead  of  the  glossy  base  paper  when  assembling  the 
print.  Simply  fix  the  paper,  without  exposure  and  thoroughly  wash  it. 

A  very  interesting  detailed  description  of  the  Defender  Chromatone  Process,  its 
principles  and  practical  application  is  offered  in  a  booklet  that  should  be  secured  from  the 
Defender  Photo  Supply  Co.  of  Rochester,  N.  Y. 

The  above  described  Chromatone  Process  of  making  color  photographic 
prints  is  one  in  which  color  images  are  formed  on  three  transparent  media 
which  are  permanently  superimposed  upon  paper,  forming  a  print  consist- 
ing of  a  number  of  layers. 

Wash-off  Relief  Process 

Another  method,  in  which  relief  images  are  formed  on  transparent 
supports  and  dyed  with  water  soluble  dyes,  and  in  which  only  dye  images 
are  transferred  to  paper,  known  as  the  Eastman  Wash-Off  Belief  Process 
is  offered  to  our  readers.  This  comparatively  new  but  thoroughly  tried 
process  is  readily  mastered. 

The  Process  in  Brief 

For  the  Eastman  Wash-Off  Relief  Process  of  printing  in  natural  colors,  three-color 
separation  negatives  are  required.  These  are  employed  to  make  prints,  by  contact  or  en- 
largement onto  Eastman  Wash-Off  Relief  Film.  In  either  method  of  printing,  the  ex- 
posure is  made  through  the  support  of  the  relief  film.  Positive  silver  images  are  first 


Color  Photography 

developed  in  the  relief  films,  and  are  then  bleached  in  a  bichromate  solution.  This  bleach 
renders  the  gelatine  of  the  photographic  emulsion  insoluble  in  the  regions  of  the  silver 
image.  Then,  by  washing  in  warm  water,  all  of  the  soluble  gelatin  is  removed,  and  relief 
images  in  hardened  gelatin  are  left  adhering:  to  the  supports.  These  are  fixed  in  hypo 
and  thoroughly  washed.  The  three  relief  images  are  then  dyed  in  the  Eastman  Three- 
Color  Printing  Dyes,  A,  B  and  G.  The  dyed  positives  may  be  superimposed  in  register  to 
form  a  three-color  transparency,  or  they  may  be  used  in  the  imbibition  transfer  process  to 
make  three-color  prints  on  paper.  To  transfer  the  dyes  to  paper,  each  dyed  positive  is 
squeegeed  in  turn  onto  a  wet  paper  bearing  a  mordanted  gelatin  coating.  A  natural-color 
print  in  ti'ansparent  and  stable  dyes  is  thus  produced. 

The  Negative 

Three-color  separation  negatives  are  made  directly  from  the  subject 
(or  from  Kodachrome  positive  transparencies  as  described  earlier) 
on  Wratten  &  Wainwright  Panchromatic  Plates,  Eastman  Portrait  Pan- 
chromatic Film,  Eastman  Super- Sensitive  Panchromatic  Film,  Eastman 
Commercial  Panchromatic  Film,  or  Eastman  Panatomic  Film  through 
Wratten  Filters,  A,  B,  and  C5  (Nos.  25,  58  and  47  respectively). 

The  negatives  should  he  exposed  with  clue  regard  for  the  filter  factors 
corresponding  to  the  light  source  employed,  and  all  of  the  plates  or  films 
must  be  uniformly  developed.  The  inclusion  in  the  subject  of  a  scale  of 
greys  near  an  edge  of  the  field  assists  greatly  in  obtaining  correct  exposure 
and  development  of  the  negatives,  or  in  making  suitable  adjustments  in 
Ihe  printing  in  case  slight  errors  of  density  or  contrast  are  found  in  the 
negatives.  If  the  set  is  correctly  exposed  and  developed,  any  given  step 
on  a  scale  of  greys  should  have  the  same  density  in  each  of  the  three 
negatives.  The  contrast  or  "gamma"  for  the  scale  of  greys  is  preferable 
0.8  to  1.2. 

Step-by-Step  Procedure  of  the  Printing  Process 

Making  the  Relief  Positives 

1.  Print  by    contact    or   projection    through    Wratten    Filter   No.    35    onto    three    Eastman 
Wash-Off  Relief  Films,   exposing  through   relief-nlm   supports. 

2.  Develop  5  minutes  in  Formula  D-ll  at  65°F.    (18°C.). 

3.  Wash  10  minutes  in  running  water  at  not  more  than  70°F.    (21°C.). 

4.  Bleach    completely    (about    2   minutes)    in    Solution    R-10    at    65°F.    (18° C.). 

5.  Develop   4   minutes    in   water   at   110°F.    (43°C.). 

6.  Fix   1   minute  in   Bath   F-24. 

7.  Wash    5    minutes    in    running   water. 

8.  (Optional)   Bleach  brown  stain  by  bathing  1  minute  in  Permanganate  Reducer  R-2. 

9.  (Optional)    Wash  3  minutes   in   running  water. 

10.  (Optional)   Clear  by  replacing  in   Bath  F-24  for  1   minute. 

11.  (Optional)   Wash  5  minutes  in  running  water. 

12.  (Optional)   Dry. 

Dyeing1  the  Reliefs. 

13.  Dye  reliefs  in  solutions  of  Dyes  A,   B   and   C  for   30   minutes. 

14.  Rinse  in  dilute  acetic  acid  of  concentrations  given. 

15.  Superimpose   dyed   reliefs   for   inspection. 

16.  If   necessary,    give    corrective   treatment. 
Finishing    Transparencies. 

17.  Dry  Films. 

18.  Varnish,  if  desired,   and  dry. 

19.  Register  films   in    superposition. 

20.  Bind  films  between  cover  glasses. 


Making   Imbibition    Transfers   to   Paper. 

21.  Prepare   paper   in   advance,    or   during   dyeing  of    reliefs. 

22.  Transfer   magenta   dye. 

23.  Transfer   blue-green    dye. 

24.  Transfer  yellow  dye. 

25.  Dry  print  between  blotters   or   on  ferrotype   tin. 


Dissolve  all  chemicals  in  the  order  given. 

Developer     (D-ll) 

Avoirdupois  Metric 

Water    (about    125°F.)     (52°    C.) 64  ounces  2.0  liters 

Elon     60  grains  4.0  grams 

Sodium    Sulphite,    Desiccated 10  ounces  300.0  grams 

Hydroquirione      1  ounce  85  grains  36.0  grams 

Sodium    Carbonate,    Desiccated 3  ounces  145  grains  100.0  grams 

Potassium    Bromide       290  grains  20.0  grams 

Water     to     make 1  gallon  4.0  liters 

Use   without   dilution. 

Wash-Off  Relief  Bleaching  Solution     (R-10) 

Stock  Solution  A 

Avoirdupois  Metric 

Water     16       ounces  500.0  cc. 

Ammonium    Bichromate     290       grains  20.0  grams 

Sulphuric    Acid    C.P 3Mz  drams  14.0  cc. 

Water  to  make   32       ounces  1.0  liter 

Stock  Solution  B 

Sodium  Chloride  (table  salt)    !*/£  ounces  45.0  grams 

Water  to  make  32      ounces  1.0  liter 

For  use,  take  1  part  of  A,   1  part  of  Bt  and  10  parts  of  water. 

Non-Hardening  Fixing  Bath     (F-24) 

Avoirdupois  Metric 

Water    (about  125°  F.)    (52°  C.)    16  ounces  500.0  cc. 

Hypo 8  ounces  240.0  grams 

Sodium    Sulphite,    Desiccated    145  grains  10.0  grams 

Sodium    Bisulphite     365  grains  25.0  grams 

Water    to    make     32  ounces  1.0  liter 

Permanganate  Reducer     (R-2) 
Stock  Solution  A 

Avoirdupois  Metric 

Water 32       ounces  1.0  liter 

Potassium    Permanganate     1%  ounces  52.5  grams 

Stock  Solution  B 

Water     32  ounces  1.0  liter 

Sulphuric  Acid,  C.P 1  fluid  ounce       32.0  cc. 

For  use,  take  1  part  of  stock  solution  A,  2  parts  of  stock  solution  B,  and  64  parts  of 

Important:  When  preparing  stock  solution  B,  always  add  the  acid  slowly  to  the  water 
while  stirring  the  water  rapidly.  Never  add  the  water  to  the  acid,  or  the  solution  may 
boil  over  and  spatter  on  tha  hands  or  face,  causing  serious  burns, 

Chromium  Intensifier     (IN-4) 
Stock  Solution 

Avoirdupois  Metric 

Potassium  Bichromate    3  ounces  90.0  grams 

Hydrochloric   Acid   C.P 2  fluid  ounces  64.0  cc. 

Water   to   make    32  ounces  1.0  liter 


Color  Photography 

For  use,  take  1  part  of  stock  solution  to  10  parts  of  water.  Bleach  thoroughly,  then 
wash  for  five  minutes  and  redevelop  fully  (5  to  10  minutes)  in  artificial  light  or  daylight 
in  any  quick-act  ins;,  non-staining;  developer  containing  the  normal  proportion  of  bi'omide, 
such  as  Formula  D-ll,  diluted  1:3.  Then  wash  thoroughly  and  dry.  Greater  intensification 
can  be  obtained  by  repeating  the  process.  The  degree  of  intensification  can  be  controlled 
by  varying  the  time  of  redevelopment. 

Table  of  Dilutions  of  Acetic  Acid 

Concentra-  Amount  of  Acetic  Acid 

tion  in  %                 Glacial    Acetic    Acid  28%  Commercial    Acetic    Acid 

1/10%                  1  cc.    diluted    to    1    liter,  or                        3.6  cc.   diluted  to   1   liter,   or 

%  fluid    dram    diluted    to  1  fluid    dram    diluted     to 

32  ounces  32  ounces 

Vz%                 5  cc.    diluted    to    1    liter,  or                         18  cc.   diluted   to   1   liter,   or 

1*4  fluid  drams  diluted  to  5  fluid    drams    diluted    to 

32  ounces  32  ounces 

5%                  50  cc.    diluted    to    1    liter,  or                       180  cc.   diluted  to   1   liter,   or 

13  fluid  drams  diluted  to  5%  fluid   ounces    diluted    to 

32  ounces  32  ounces 

Aluminum    Sulphate    Solution    for    Mordanting    Paper     (M-l) 

Avoirdupois  Metric 

(A)  Aluminum     Sulphate     6%  ounces  200  grams 

Water    to    make    32       ounces  1  liter 

(B)  Sodium    Carbonate,     ..Desiccated 1  ounce  145  grains  40  grams 

Water    to    make     16       ounces  500  cc. 

Add  B  slowly  to  A,  stirring  well  during  the  addition.  A  white  precipitate  is  at  first 
formed,  but  this  dissolves  upon  stirring.  If  a  trace  should  remain,  it  can  be  filtered  out 
with  a  rapid  filter  paper. 

5%   Sodium  Acetate  Solution 

Dissolve  Sodium  Acetate.  Anhydrous  (E.  K.  Co.).  50  grams  in  950  cc.  water,  or 
dissolve  Sodium  Acetate,  Anhydrous  1-2/3  ounces  in  32  ounces  of  water. 

1%  Ammonia  Solution 

Add   one   part   by  volume   of   strong   ammonia   water  to    100    parts   of   water. 

Varnish   Formula   for   Color-Film  Transparencies     (V-l) 

Avoirdupois  Metric 

Gum    Sandarac    365       grains  25  grams 

N-Butyl    Alcohol     G*/>  fluid  ounces  200  cc. 

Castor   Oil    1%  fluid  drams          5  cc. 

Oil    of    Lavender     14  fluid  dram  1  cc. 

Warm  the  gum  sandarac  and  butyl  alcohol  together  until  the  sandarac  has  been 
entirely  dissolved.  (Caution:  Butyl  alcohol  is  inflammable,  and  should  not  be  heated  over  an 
open  flame.)  Then  filter  the  solution  through  a  fine,  lintless  cloth,  add  the  castor  oil 
and  the  oil  of  lavender,  mix  thoroughly,  and  cool  before  using.  The  oil  of  lavender  may 
be  omitted  if  the  odor  of  the  castor  oil  is  not  objectionable. 

The  Eastman  Wash-Off  Relief  process  is  essentially  very  simple,  once 
understood  and  acquired.  However  detailed  instructions  and  specific  infor- 
mation covering  every  step  of  the  procedure  are  absolute  prerequisites  of 
success  in  making  color  prints  by  this  method.  Accordingly  the  editors 
feel  that  they  are  performing  an  important  duty  towards  their  readers  in 
briefly  presenting  the  outline  of  the  process.  It  is  suggested  that  those 
seriously  interested  address  the  Graphic  Arts  Department  of  the  Eastman 
Kodak  Co.,  Rochester,  New  York,  requesting  latest  issue  of  pamphlet 
entitled  "Color  Printing  with  Eastman  Wash-Off  Relief  Film".  The  Eastman 
Wash-Off  Relief  Process  is  being  constantly  improved  and  latest  informa- 
tion should  be  secured  from  the  Eastman  Kodak  Company. 




Face  Lift  Operation 

Henry  M.  Lester 


jfp.  t  ,,#«#**  -    <<    &*^&Mulll,>f'f>*» 

'%^J*    '     '  ^^^w*^ 

Pig.  182     Transportation 

J.  D.  McCauley 




The  onetime  formal  and  rather  bitter  educational  procedure  of 
the  elementary  and  grammar  school  is  giving  way  to  the  more 
interesting  and  profitable  method  of  encouraging  the  pupil  in  self- 
activity.  The  pupil  is  placed  in  a  situation  where  it  is  desirable  to 
make  comparisons,  secure  information,  and  calculate  solutions  to 
problems,  thus  developing  a  need  for  the  use  of  letters,  words, 
figures,  and  other  symbols  of  thought.  The  term,  motivation,  is  used 
to  indicate  this  more  effective  training  procedure. 

Visual-sensory  aids  to  instruction  perform  a  definite  function  in 
this  procedure.  A  simple  picture,  carefully  chosen,  may  bring  a 
series  of  voluntary  oral  discussions,  written  compositions  and  mathc- 


matical  calculations  equivalent  to  many  of  the  former  fearful  assign- 
ments of  themes  and  sums.  Objects,  themselves,  may  be  used  even 
more  effectively,  but  frequently  it  is  impossible  to  have  the  real 
objects  available.  Representations  of  those  objects  are  next  in  value, 
and  the  photograph  is  one  of  the  most  economical  of  all  represen- 
tations. The  photograph,  properly  made  or  chosen,  may  be  even 
better  than  the  object,  especially  for  group  instruction.  Teachers 
are  realizing  this  and  are  beginning  to  develop  series  of  pictures  for 
class  instruction,  very  much  as  they  might  select  reference  books, 
magazines  and  other  aids. 

Pupil-participation  is  exceedingly  important  as  a  motivating 
agency.  If  the  pupil,  even  the  unruly  one,  can  be  made  to  feel  that 
his  presence  and  cooperation  are  important  in  the  scheme  of  things, 

Pig.  183  This  picture  by  Creigh- 
ton  Peet  will  gain  the  coopera- 
tion and  interest  of  young  Child- 
ren very  Quickly  and  Stimulate 

life  takes  on  a  new  meaning  to  him  and  education  becomes  something 
more  than  an  endurance  contest.  Pupils  may  collect  specimens,  clip 
pictures  from  magazines  and  newspapers,  build  collections  of  hobbies, 
and  do  many  things  which  will  serve  a  dual  purpose:  (1)  develop 
an  intense  working  interest  on  the  part- of  the  pupil,  and  (2)  develop 
a  collection  of  materials  which  will  be  of  inestimable  value  in  teaching 
present  and  future  groups. 

One  prominent  visual  instruction  director  takes  pictures  of  his 
pupils  in  special  situations.  He  secures  a  good  picture  of  a  pine- 
apple field,  for  example.  Next,  he  takes  a  picture  of  a  member  of  the 
class  in  which  the  picture  of  the  pineapple  field  is  to  be  used.  By 
clever  photographic  procedure,  he  combines  the  two  to  make  a  picture 
of  that  pupil  in  a  pineapple  field.  The  combined  picture  is  trans- 
ferred to  a  lantern  slide  for  projection.  The  pupil  is  instructed  in 
advance  that  he  or  she  will  be  expected  to  tell,  during  the  projection 
of  the  picture,  just  how  it  seems  to  be  in  a  pineapple  field.  In  order 


Fig.  184    Indian  Children  Fig.  185     Negro  Children 

Pictures  to  show  how  the  children  of  different  races  look,  live,  and  play 

to  do  this  satisfactorily,  that  pupil  must  find  out  as  much  as  possible 
about  pineapples.  Although  photographic  trickery  is  used  to  build 
a  false  situation,  that  situation  proves  to  be  a  great  motivating  in- 
fluence and  increases  the  interest  of  the  entire  group  in  that  subject. 
A  similar  procedure  might  be  adapted  to  many  situations. 

Teachers  are,  properly,  the  most  extensive  travelers  of  any  in 
professional  work.  Travel  does  much  to  broaden  the  outlook  and 
increase  the  efficiency  of  the  teacher.  Some  collect  specimens  of 
various  kinds  to  be  used  later  in  teaching.  Others  gather  pictures, 
pamphlets,  curios,  and  the  like,  for  the  same  purpose.  But  there  is 

Fig.  186      Harvesting  in  Siberia 

Such  a  picture  tells  the  story  quicker  : 

Julien  Bryan 

md  better  than  a  thousand  words 


Fig.  187    Foxgloves 

A  series  of  pictures  presenting  complete  information  about  these  flowers, 
in  their  natural  environment,  flower  formation,  malformation  of  one  of  the 
blooms,  and  even  a  close-up  cross  section 

an  increasing- number. of  those  who  are  depending  upon  the  camera 

to  record  the  experiences  of  travel  which  may  aid  in  the  classroom. 

All  forms  of  plant  and  animal  life  undergo  important  changes 

during  the  summer  months.     Some  forms  complete  their  life  cycles 



during  the  period  when  pupils  are  on  vacation  from  formal  instruc- 
tion. Things  are  happening  which  the  child  may  not  notice  or  may 
not  understand.  The  brilliant  colors  of  midsummer  are  gone  when 
the  importance  and  functions  of  color  among  living  things  are  dis- 
cussed in  the  classroom  sometime  between  September  and  June.  A 
camera  which  will  record  the  changes,  including  accurate  reproduc- 
tion of  color,  and  will  make  them  available  for  later  use  in  the  class- 
room becomes  one  of  the  most  valuable  assistants  any  teacher  could 
choose.  The  camera  which  would  be,  satisfactory  for  this  type  of 
photography  might  be  used  equally  well  to  record  any  other  things 

Fig.  188       Threshing  in  New  Mexico  Willard  D.  Morgan 

In  the  little  town  of  Chimayo,  north   of   Santa  Fe,  this  interesting 
threshing  scene  was  photographed 

of  interest,  including  pictures  of  people,  buildings,  landmarks,  points 
of  historical  interest,  rock  formations,  trees,  animals,  and  the  like. 

Inasmuch  as  teachers  are  not  endowed,  normally,  with  unlimited 
funds  for  such  activities,  it  is  necessary  that  photographic  equipment 
be  selected  which  will  accommodate  almost  any  photographic  task  and 
do  it  inexpensively.  The  Leiea  camera  is  meeting  such  requirements 
and  is  becoming  increasingly  popular  among  those  who  realize  the 
potential  value  of  pictures  in  teaching. 
Educational  Use  of  Pictures 

It  seems  proper,  at  this  point  in  the  discussion,  to  mention  some 
of  the  things  to  be  observed  in  selecting  or  making  pictures  to  be 
used  as  visual  aids.  In  the  first  place,  the  mere  showing  of  a  picture 


to  a  pupil  or  to  a  class  may  be  an  absolute  waste  of  time  except  as  it 
may  inject  variety  into  an  otherwise  dull  classroom  situation.  An 
intelligent  teacher  would  not  inject  the  study  of  Chaucer  into  a 
class  in  the  lower  grades.  Neither  would  that  teacher  assign  prob- 
lems in  physics  to  a  class  in  elementary  mathematics.  It  is  fully 
as  important  to  select  the  proper  type  of  picture  for  use  in  any 
given  situation.  The  few  simple  suggestions  noted  below  might  well 
be  observed  in  outlining  plans  for  the  selection  and  use  of  pictures 
in  the  classroom: 

1.  Pictures  selected  for  educational  use  should  be  within  the  age,  or  grade- 
level  of  the  pupils  with  whom  the  pictures  are  to  be  used.    (A  picture  of 
the  Parthenon  would  mean  little  to  an  elementary  group  and  a  picture  of 
Mary  Jane's  doll  house  would  not  be  appreciated  by  pupils  in  the  upper 

2.  A  few  pictures  which  are  pertinent  to  the  subject  under  discussion  would 
be  preferable  to  many.    The  use  of  too  many  pictures  is  more  likely  and 
more  harmful  than  the  use  of  too  few. 

8.  The  pictures  used  should  relate  directly  to  the  lesson  or  unit  of  instruc- 
tion and  should  contain  few  or  no  irrelevant  details.  Anything  which 
may  not  so  relate  to  the  subject  under  discussion  will  have  a  tendency  to 
detract  seriously. 

4.  Each  picture  should  contain  some  object  of  familiar  size.     A  person, 
an  article  of  clothing1,  a  pencil,  or  any  other  object  commonly  known  to 
pupils  will  aid  in  conveying  a  correct  impression  of  the  primary  subject 
of  the  picture. 

5.  Pictures  should  indicate  action  whenever  action  will  aid  in  presenting  a 
natural  situation.    Animals  moving  about,  children  at  play,  farmers  at 
work  in  their  fields,  make  excellent  photographs  and  are  vastly  more 
interesting  than  posed  pictures. 

6.  Pictures  must  be  mechanically  correct  and  of  sufficient  size  to  be  viewed 
without  eye  strain.     This  applies  particularly  to  projected  pictures  but 
might  be  applied  as  appropriately  to  photographs  and  enlargements. 

There  are  many  sources  from  which  organized  picture  units  may  be 
secured.  Some  are  for  sale  and  some  may  be  borrowed.  The  school  which 
is  able  to  purchase  an  adequate  supply  of  pictorial  materials  for  use  among 
its  teachers  places  those  teachers  in  a  fortunate  situation.  However,  if  it 
should  be  possible  for  each  school  to  purchase  a  liberal  supply  of  available 
pictures,  there  would  still  remain  many  occasions  for  the  use  of  a  camera 
to  record  special  activities  and  scenes  of  local  importance  or  for  special 
application  to  teaching  problems.  Inasmuch  as  no  school  is  able  to  pur- 
chase all  desirable  material  and  many  schools  are  able  to  purchase  little 
or  none,  a  suitable  camera  becomes  highly  important  to  those  teachers  who 
desire  to  -present  instructional  material  in  an  interesting  and  effective 

The  Leica  Camera 

The  cost  of  producing  suitable  pictures  for  school  use  has  been 
a  hindrance  to  the  wider  use  of  appropriate  illustrations.  The  avei- 
age  camera  will  produce  a  reasonably  good  picture  under  ordinary 


Fig.  189    Dramatics  Montage  Designed  by  Barbara  Morgan 

From  1936  Pean,  school  annual,  Phillips  Exeter  Academy,  New  Hampshire.  The  indi- 
vidual shots  are  from  the  productions  of  "Macbeth  and  Androcles  and  the  Lion"  and  were 
photographed  by  students  of  Phillips  Exeter  Academy.  *• 

Teaching-  the  Deaf  to  Speak 

Summar  50mm  lens,  f  :2.2,  1/3,  E.  K.  Super  X  film. 


J.  Winton  Lemen 


conditions  but  that  picture  is  not  ready  for  use  in  the  classroom. 
It  is  too  small  to  be  clear  in  all  its  details  and  it  is  not  in  proper 
form  for  easy  enlargement  through  projection.  If  enlarged  as  a 
photograph,  the  cost  is  prohibitive,  and  it  must  be  transferred  to 
glass  or  film  for  suitable  projection.  The  latter  procedure  requires 
special  apparatus  and  materials,  involving  considerable  expense. 

The  Leica  camera,  on  the  other  hand,  is  capable  of  producing 
film  strips  for  projection  at  a  ridiculously  low  figure.  The  teacher 
who  will  follow  a  few  simple  directions  can  prepare  such  pictures 
at  a  cost  which  will  range  from  four  to  six  cents  per  picture  using 
inexpensive  apparatus  for  developing  and  printing.  Furthermore, 
this  same  camera  may  be  used  to  copy  large  or  small  pictures  for 
similar  projection.  The  Leica  camera  will  photograph  anything 
from  very  small  miscroscopic  organisms  to  the  largest  things  in  the 
known  world.  The  chapters  on  Copying  and  the  making  of  positives 
give  more  complete  information. 

If  it  should  seem  desirable  to  use  photographs  of  any  convenient 
size,  or  of  various  sizes,  such  enlargements  may  be  made  by  using 
enlarging  apparatus  which  is  both  inexpensive  and  simple  to  operate. 
Eefer  to  the  chapter  on  Enlarging.  The  cost  of  such  enlargements 
will  be  very  little  more  than  the  cost  of  the  negative  for  the  average 
camera  and  the  enlargements  may  be  made  to  conform  to  any  desired 
size  or  type.  The  negatives  may  be  filed  in  small  space,  cataloged, 
and  used  for  reference  purposes  as  needed. 

If  it  should  be  desirable  to  make  and  color  lantern  slides  of  any ^ or 
all  of  the  negatives,  the  procedure  is  more  economical  than  the  production 
of  slides  by  any  other  method,  and  the  results  are  highly  satisfactory-  For 
ordinary  classroom  purposes,  the  double-frame  film  slide  produced  by  con- 
tact printing  of  Leica  negatives  will  be  almost  as  satisfactory  as  the  glass 
slide  and  will  be  much  less  expensive. 

Some  teachers  Jind  that  their  regular  duties  require  so  much  time 
that  it  is  impractical  to  use  the  small  amount  of  time  required  to  develop 
and  print  or  enlarge  miniature  pictures.  In  such  cases  the  most  logical 
solution  of  the  problem  is  to  organize  a  small  camera  club  of  older  stu- 
dents who  may  be  interested  in  photography.  Such  a  club  will  serve  many 
purposes.  It  will  train  its  members  to  apply  leisure  time  in  an  interest- 
ing and  profitable  activity.  It  will  develop  a  greater  interest  in  the  pro- 
duction and  use  of  pictures  throughout  the  school.  It  will"  build  a  useful 
and  valuable  collection  of  pictorial  materials  at  low  cost  to  the  school. 

Convenience  is  another  attribute  of  the  miniature  camera  which  should 
be  given  careful  consideration.  It  may  be  carried  in  a  handbag,  in  the 
pocket,  or  suspended  on  a  small  strap.  It  is  always  ready  for  action  and 
may  be  adjusted  to  any  special  situation  quickly.  It  is  simple  to  operate 
and  all  necessary  adjustments  are  made  in  less  time  than  is  required  to 
mention  it. 


Fig.  190  Bark  Splitting- 
cm  a  Five  Year  old  Peach 
Tree  from  the  low  Tem- 
peratures of  1929-30.  Note 
the  Healing  over  of  the 
Exposed  Area 

Photo  by  M.  J.  Dorsey 

The  adaptability  of  the  miniature  camera  is  the  greatest  of  all.  The 
various  simple  attachments  which  are  available  to  adapt  it  to  special  situa- 
tions cover  every  possible  requirement.  The  wide  range  of  available  lenses 
will  accommodate  anything  anyone  could  photograph  with  any  other  camera 
or  group  of  cameras.  In  all  this,  the  cost  of  operation  is  much  less  than 
would  be  the  cost  of  operating  the  ordinary  pocket  camera  which  uses 
rolls  of  six  to  ten  or  twelve  exposures. 

The  Miniature  Camera  in  Special  Subjects 

Agriculture.  One  of  the  chief  handicaps  of  the  teacher  of 
agriculture  in  the  average  school  is  that  the  principal  crops  grow, 
fertilize  and  mature  during  the  months  of  the  school  vacation  period. 
The  animal  life  of  the  farm  has  undergone  important  changes.  There 
are  many  printed  reports  of  what  has  taken  place  and  the  teacher 
may  be  able  to  describe  the  developments  in  an  interesting  manner. 
However,  a  pictorial  record  of  those  changes  could  be  made  with  the 
Leica  camera  and  used  to  enliven  the  classroom  discussions  of  various 
farm  crops  and  animals. 

The  agriculture  teacher  who  goes  to  fairs  and  other  exhibitions 
of  the  best  in  farm  products  might  not  be  able  to  bring  samples  of 



those  products  before  his  classes  for  study.  It  would  be  rather  simple 
to  make  a  complete  series  of  pictures  of  the  most  important  ones. 
The  cost  would  be  but  a  few  cents  per  picture  and  the  possibilities 
would  be  unlimited.  The  convenience  of  small  size  makes  it  possible 
to  carry  the  camera  constantly  for  the  purpose  of  photographing 
anything  which  might  be  of  importance. 

A  further  great  advantage  of  the  miniature  camera  is  the  ease 
with  which  it  may  be  used  to  copy  charts,  graphs,  drawings,  prints, 
or  other  graphic  materials  for  projection  or  reproduction.  Frequent- 
ly, valuable  charts  are  accessible  for  study  but  may  not  be  taken 
from  library  or  private  collections.  In  practically  all  such  case^, 
permission  to  photograph  those  charts  may  be  obtained.  The  photo- 
graphs of  the  charts  may  be  projected  for  study  and  are  really  more 
useful  than  the  original  charts  in  some  instances.  The  miniature 
camera  is  ideal  for  such  copying. 

Biological  Sciences.  The  possible  uses  of  the  Leica  camera  in 
preparing  materials  for  use  in  teaching  the  biological  sciences  are 
unlimited.  Photographs  and  photographic  enlargements  of  speci- 
mens of  all  sizes,  types  and  colors  may  be  photographed  and  pro- 

Pig.  191     A  Parent  Bird  and  Family.  "Photo  by  Charles  A.  Proctor 

Fig.  192  (left)  Cotton  Blossom  and  Plant.  This 
Picture  and  the  two  Above  give  a  Quick  Impres- 
sion of  the  Subject  by  Eliminating  all  Unessen- 
tial Details 

jected  or  reproduced  accurately.  A  series  of  photographs  showing- 
successive  changes  in  living  forms  may  be  made  at  little  expense. 
Flowers,  birds,  roots,  leaves,  seeds,  insects,  animals,  and  all  usual 
types  of  microscopic  cross-sections,  plants,  and  animalcules  may  be 
photographed  with  ease  and  accuracy.  Teachers  who  conduct  re- 
search during  vacation  periods  or  who  may  desire  to  produce  special 
pictures  for  class  use  will  be  unable  to  secure  a  substitute  for  the 
miniature  camera  which,  will  fill  the  requirements  at  such  low  expense. 
Languages.  Objects  are  becoming  increasingly  important  in  the 
building  of  a  vocabulary.  Projected  pictures  may  be  used  in  all 
classes,  from  the  lowest  elementary  grades  through  the  foreign  Ian- 

Fig.  193     Peregrine  Falcons  Charles  A.  Proctor 

A.  mother  and  her  youngster  give  the  photographer  a  tough  look 



guage-  groups  in  colleges  and  universities,  for  the  purpose  of  fixing 
new  word  symbols  or  clarifying  the  meaning  of  the  old.  The  lan- 
guage teacher  who  has  long  desired  a  collection  of  representative 
pictures  for  use  during  the  teaching  of  vocabulary  may  use  the  Leica 
camera  to  copy  such  pictures  from  books,  magazines,  travel  bulle- 
tins, and  the  like.  Furthermore,  those  who  travel  will  be  able  to 
prepare  adequate  collections  of  original  photographs  at  low  cost. 

A  projected  picture  in  the  classroom  is  one  of  the  most  potent 
stimulators  of  oral  expression  and  may  be  made  the  central  topic 
for  a  major  part  or  all  of  a  recitation  period.  All  such  expression 
will  but  tend  to  develop  greater  facility  in  the  use  of  words,  regard- 
less of  the  language  employed. 

Another  profitable  use  of  the  Leica  camera  in  language  instruc- 
tion would  be  for  photographing  and  projecting  charts  of  word 

Fig.  194       The  People  of  Tibet 

Harrison  For  man 

These  pictures  are  full  of  details.  Note  man  in  the  background  holding-  his 
hands  over  his  face...  why?  A  market  scene. .  .ornaments. .  .dress. .  .super- 

forms  and  endings,  thus  eliminating  the  tedious  procedure  of  copying 
such  material  on  blackboards  or  on  charts.  With  a  little  camera,  a 
little  care,  and  a  little  energy,  the  energetic  teacher  will  be  able  to 
increase  the  effectiveness  of  instruction  with  a  saving  in  time  to  all 

Geography.    The  myriad  possible  uses  of  the  miniature  camera 
for  the  preparation  of  materials  to  be  used  in  teaching  geography 


Fig.  195     The  Concrete  Mixer  W.  H.  Friedrich 

An  excellent  action  picture  which  shows  the  mixer  in  actual  operation  with  humans  to 
give  the  scale  and  a  more  personal  quality 

stagger  the  imagination.  Pictures  of  people  at  work  and  at  play 
in  all  corners  of  the  earth  may  be  photographed  by  those  fortunate 
enough  to  travel  widely  or  may  be  copied  from  suitable  photographs. 
These,  projected  in  the  classroom,  are  second  in  value  to  travel  in 
giving  true  concepts  of  the  way  others  live. 

The  same  Leica  camera  may  be  used  to  copy  detailed  outline 
maps  which  may,  in  turn,  be  projected  against  a  white  cardboard  or 
blackboard  for  study  and  for  fixing  locations.  Pictures  are  exceed- 
ingly valuable  in  the  study  of  human  relations  and  the  miniature 
camera  offers  the  most  economical  means  of  providing  those  pictures. 

Local  geography  is  neglected  frequently  but  could  be  utilized 
to  good  advantage.  Those  features  which  are  difficult  to  observe  by 
excursion  or  field  trip  may  be  photographed  and  brought  into  the 
classroom.  The  fact  that  such  pictures  are  of  local  situations  will 
tend  to  increase  their  value  as  related  to  the  teaching  problem. 

History.  Again,  the  teacher  who  travels  may  produce  a  series 
of  pictures  which  would  be  of  inestimable  value  in  the  classroom. 
It  would  not  be  necessary  to  travel  widely.  Local  history  forms  an 
important  part  of  the  instruction  in  all  schools  and  could  be  made 
a  great  motivating  agency  in  both  oral  and  written  composition. 
Pictures  of  landmarks  of  early  development,  homes  of  famous  per- 



sons,  federal  and  state  governmental  buildings,  and  of  any  number 
of  other  places  could  be  obtained  either  by  direct  photography  or  by 
copying  from  publications  of  all  kinds. 

The  Leica  camera  is  so  inconspicuous  and  convenient  to  use  that 
many  are  able  to  collect  excellent  assortments  of  pictures  of  im- 
portant figures  in  the  events  of  the  day.  The  possible  use  of  such 
a  camera  to  produce  pictures  for  use  in  connection  with  the  study 
of  current  events  are  many. 

Industrial  Arts.  Here  the  Leica  camera  may  be  used  to  good 
advantage  for  the  preparation  of  either  elementary  or  advanced 
work.  Certain  master  drawings  might  be  photographed  and  pro- 
jected on  a  screen  for  group  study,  a  far  more  satisfactory  method 
than  to  make  a  drawing  large  enough  for  the  class  to  study,  and 
incomparably  better  than  passing  an  outline  or  a  drawing  from  one 
student  to  another.  Furthermore,  materials  thus  organized  for  pre- 
sentation could  be  preserved  in  small  space  and  brought  out  for 
service  as  needed. 

One  instructor  in  engineering  in  a  mid-western  university  uses 
a  miniature  camera  to  copy  drawings  and  outlines  of  special  problems 
and  their  solutions.  Such  problems  are  illustrated  and  discussed  in 
the  professional  magazines  and  the  former  method  of  this  instructor 
was  to  draw  enlarged  charts  of  ample  size  for  the  class  to  discuss 


Fig.  196     How  Are  the  Bones  and  Fragments  of  a  Prehistoric  Animal 
Assembled  and  Mounted  ?     Photo  by  Dr.  A.  L.  Lugn 


Pig.  197  Stones  For  Grind- 
ing Corn  in  an  Arizona 
Cliff  City 

Fig.  198  Betatakin  Cliff 
Dwelling  in  Arizona.  A 
City  once  Inhabited  by 
several  Thousand  Indians. 
Photos  by  Willard  D.  Mor- 

as  a  group.  Now,  it  is  only  necessary  to  photograph  the  page  with 
the  little  camera,  make  a  print  on  film,  and  project  that  print  to 
any  desired  size.  If  charts  seem  desirable  for  use  in  the  solution  of 
similar  problems,  they  may  be  made  quickly  by  tracing  the  projec- 
tion on  suitable  paper.  The  process  is  simple,  rapid,  and  inexpensive. 
It  would  be  almost  as  easy  and  but  slightly  more  expensive  to  make 
photographic  enlargements  for  such  members  of  the  class  as  might 
require  them. 

Architecture.  This  is  the  branch  of  engineering  which  is  served  best 
by  the  miniature  camera.  Many  interesting  photographs  of  desirable 
types  of  architecture  may  be  made  at  little  cost  and  studied  at  will.  With 
one  camera  loading  of  36  pictures  it  is  possible  to  photograph  exterior,  and 
interior  views  of  a  building,  and  also  make  numerous  close  up  detail  views. 
This  strip  may  be  reproduced  on  a  filmslide  strip  for  projection  at  a  cost 
varying  from  four  to  five  cents  per  picture.  The  cost  of  making  such 
pictures  with  the  miniature  camera  is  so  little  that  various  angles  of  each 
design  may  be  recorded  at  less  than  the  cost  of  a  single  picture  of  average 
camera  size.  Small  designs  in  professional  publications  may  be  copied  and 
enlarged  to  any  desired  size.  So  long  as  the  resultant  enlargements  are 



made  for  personal  use  and  not  offered  for  distribution,  there  is  no  infringe- 
ment of  copyrights   or   question   of  unprofessional   ethics. 

Physical  Training.  Many  schools  offer  various  forms  of  corrective 
gymnastics.  Students  who  seem  to  require  correction  of  physical  defects 
or  irregularities  are  photographed  before  the  training  is  started.  They  are 
photographed  during  the  process,  until  correction  ends.  The  miniature 
camera,  producing  pictures  with  enlarging  and  projection  possibilities, 
becomes  the  first  choice  of  the  physical  training  supervisors  who  give  this 
record  work  serious  thought. 

The  photographs  of  corrective  changes  are  important  but  by  no  means 
exhaust  the  possible  adaptations  of  the  miniature  camera  to  corrective  or 
competitive  athletics.  The  Leica  camera  is  equipped  with  a  lens  and 
shutter  competent  to  photograph  all  types  of  action,  stopping  that  action 
at  any  point  for  careful  study  of  form.  In  many  instances,  such  stop- 
motion  pictures  are  as  valuable  to  the  coach  or  trainer  as  would  be  motion 
pictures  of  the  same  athlete  in  action.  These  pictures  may  be  used  effec- 
tively to  point  out  both  good  and  bad  points  in  the  form  of  the  athlete. 
The  suggestions  are  vastly  more  clear  to  him  than  if  made  orally  without 
some  form  of  supporting  illustration. 

Doctors  and  dentists  who  are  charged  with  the  responsibility  of  medi- 
cal and  dental  inspection  of  school  pupils  are  finding  the  miniature  camera 

Fig.  199       Dentition.       Child  6  to  7  Years  Old.     Primary  Teeth 
Yielding  to  Pressure  of  Secondary  Teeth.  Photo  by  Henry  M.  Lester 

to  be  of  great  value  in  photographing  physical  irregularities  which  need 
correction,  such  as  poor  teeth,  enlarged  joints,  improper  muscular  develop- 
ment, eye  defects,  and  the  like.  Peculiar  situations  may  be  photographed 
for  more  detailed  study  through  enlargement  or  projection.  It  is  possible, 
with  this  type  of  camera,  to  photograph  the  most  minute  structural  details, 
even  those  which  are  recorded  through  the  lens  of  a  microscope. 

Physical  Sciences.    Many  photographs  maybe  accumulated  which  will 
illustrate,  clearly,  the   application  of  the   simple  laws   of  science  to  the 


Fig.  200  Hog  -  Nosed 
Snake  Photo  by  J.  M. 


rather  complex  structure  known  as  civilization  and  its  environment.  Pho- 
tographs of  geologic  formations;  the  work  of  water,  wind  and  temperature 
as  they  change  the  surface  of  the  earth;  the  effect  of  volcanic  eruptions 
and  of  glacial  action;  and  of  the  application  of  physical  laws  to  the  mechan- 
ical devices  of  industry,  may  be  made  quickly  and  cheaply. 

Other  Subjects.  The  suggestions  made  above  are  but  a  few  of 
the  possible  applications  of  the  miniature  camera  to  visual  instruc- 
tion. The  enterprising  teacher  or  visual  instruction  director  will 
find  some  use  for  such  a  camera  in  connection  with  the  effective 
teaching  of  almost  every  subject  listed  in  the  curriculum.  One  of 
the  great  failings  of  textbooks  for  use  in  the  elementary  and  inter- 
mediate grades  is  that  they  contain  illustrations  covering  situations 
which  are  not  within  the  understanding  and  personal  experiences  of 
the  pupils.  It  is  not  difficult  to  supplement  the  textbook  illus- 
trations with  local  pictures  of  similar  situations,  thus  developing 
a  clear  and  logical  understanding  of  the  matters  discussed  in  the  text 
and  during  the  class  period. 

The  application  of  the  miniature  camera  to  the  problems  of  class- 
room instruction  by  no  means  exhausts  the  possibilities  of  its  use  in 
the  school  building  or  system.  For  example,  one  very  successful 
school  administrator  carries  a  minature  camera  wherever  he  goes 
among  the  various  buildings  to  observe  the  work  in  the  classrooms 
or  to  inspect  the  school  plant.  When  he  notices  an  unusually  fine 
type  of  project,  he  photographs  it.  If  some  student  has  completed 
an  outstanding  piece  of  work,  he  makes  a  picture  of  it.  If  an  altera- 
tion or  a  repair  is  needed  in  a  school  building  or  among  its  equip- 
ment, he  may  take  several  pictures  of  the  situation.  The  resultant 



pictures  are  prepared  for  projection  before  teachers'  meetings,  the 
board  of  education,  the  building  committee,  or  before  any  others  who 
may  be  interested  in  the  work  or  welfare  of  the  schools.  These  pic- 
tures become  a  permanent  record  of  progress,  frequently  quite  valu- 
able in  clarifying  misimpressions  among  those  who  are  not  thoroughly 
informed  concerning  conditions. 

The  Leica  camera  is  almost  ideal  for  the  production  of  pictures 
of  school  activities  to  be  used  for  all  types  of  publicity.  Although 
the  school  annual  is  becoming  less  important  to  student  life  each 
year,  there  are  local  and  school  papers  and  periodicals  which  make 
good  use  of  interesting  pictures.  Such  pictures  can  be  made  with 
this  camera  at  a  cost  of  a  few  cents  each.  It  is  almost  certain  that 
many  more  good  pictures  will  be  available  for  such  purposes  than  if 
the  cost  should  be  several  times  that  amount. 

The  school  which  may  desire  to  make  the  most  effective  use  of 
pictures  will  find  many  uses  for  the  miniature  camera.  Furthermore, 
the  cost  of  operation  will  be  but  a  fraction  of  the  cost  of  usual  types 
of  pietiire  making.  The  individual  teacher  or  supervisor  who  may 
be  interested  in  building  collections  of  illustrative  materials  for  class- 
room use  will  find  the  miniature  camera  to  be  an  economical  answer 
to  the  problem  of  covering  unlimited  demands  with  a  limited  budget^ 

Fig.  201     Rock  Structure,  Segi  Canyon,  Arizona,  Showing  Horizontal 
and  Vertical  Structure.    Photo  by  W.  D.  Morgan 


Dress  Patterns  in  the  Making  Henry  M.  Lester 

Drilling  the  Guide  Perforations  and  Cutting  a  "Lay"  of  One  Thousand 

Summar  50mm  lens,  1/60  second  at  f  :2.2,   Super-X  Film 

Courtesy  of  Butterick  Company 




Modern  scholarship  demands  of  the  research  worker  of  today 
impeccable  evidence  to  substantiate  his  assertions.  Such  evidence  can 
very  rarely  be  presented  in  the  form  of  originals  of  historical  mate- 
rial. True  copies  are  therefore  required.  These  not  only  must  be 
good  and  accurate  reproductions;  they  must  be  obtained  speedily  and 
effectively.  The  Leica  camera  conveniently  fulfills  these  require- 

At  one  time  the  student  spent  the  greater  part  of  his  day  in 
laboriously  copying  his  finds  or  discoveries.  Materials  of  the  most 
varied  character — illegible  letters,  worn  diaries,  old  faded  news- 
papers, statistical  tables,  and  intricate  election  returns — may  be 
copied.  These  records  can  be  secured  photographically  far  more  effi- 
ciently and  in  incomparably  shorter  time.  Subsequent  ability  to 
enlarge  to  almost  any  size  is  an  added  advantage  as  it  greatly  con- 
tributes to  the  legibility  of  such  records. 

There  can  never  be  a  question  concerning  the  accuracy  of  repro- 
duction; not  only  the  form  of  the  original  is  retained  in  such  a  copy 
but  frequently  even  its  spirit  and  intent. 

The  research  worker,  when  he  comes  to  writing,  need  not,  as  he 
must  when  working  from  typed  copies,  wonder  if  the  typist  or  the 
original  writer  made  the  strike-over,  the  omission,  the  abbreviation, 
the  cancellation,  the  interpolation,  or  any  of  the  peculiarities  which 
mark  all  human  documents.  The  genuineness  of  signatures  and  hand- 
writing and  even  the  character  of  the  paper  used  may  be  easily 
authenticated.  There  can  be  no  doubt  as  to  whether  a  letter  was 
handwritten,  typed,  or  printed;  that  a  letter  was  dictated  and 
signed  in  his  absence  is  easily  discovered.  Such  apparently  trivial 
but  sometimes  important  points  as  whether  the  address  given  on  a 
letter  was  merely  a  printed  name  or  a  part  of  the  written  manuscript 
itself  are  readily  established.  Quotations  in  the  final  *copy  for  a  book 
may  be  checked  against  the  original  Document. 

A  very  important  asset  in  copying  by  camera  is  inclusiveness. 
An  entire  manuscript  or  document  can  usually  be  recorded  as 


cheaply  and  as  quickly  as  it  can  be  extracted.  Seemingly  insignificant 
sentences  in  a  manuscript  may  take  on,  at  a  later  date,  a  meaning 
not  discerned  at  the  time  of  copying.  The  mere  fact  that  a  letter 
contains  no  mention  of  a  current  event  or  existing  condition  may 
later  prove  of  great  value  if  one  can  be  certain  that  the  omission 
was  committed  by  the  writer  and  not  the  extractor.  Adjacent  par- 
agraphs may  give  to  a  statement  meanings  or  modifications  not  per- 
ceived at  the  time  the  research  worker  copied  the  document.  By 
recording  the  entire  original,  the  camera  retains  the  proper  setting 
of  desired  extracts. 

The  camera  not  only  provides  accuracy,  speed,  and  inclusiveness 
in  copy  work;  -it  enlarges  the  field  of  research.  No  longer  must  the 
scholar  limit  his  labors  to  what  seems  at  the  moment  important;  as 
already  mentioned,  he  may  copy  somewhat  lavishly  without  adding 
perceptibly  to  the  bulkiness  of  his  material.  Maps,  charts,  and  graphs 
may  be  readily  copied  in  whole  or  in  part.  By  use  of  the  extension 
tube  the  smallest  section  of  a  chart  or  graph  may  be  lifted  out 
of  its  original  setting  and  enlarged  for  particular  study.  The 
cartoon,  most  pungent  expression  of  contemporary  opinion,  may  now 

Fig.  203       Books,    Manuscripts,   Cartoons,  and   Similar   Subjects   can   be 
Copied  for  Historical  Research.    Photos  by  James  A.  Barnes 

MAT  **  *•»"»     '*! 

THE  NATIONAL        i 




Historical  Research 

make  up  an  important  and  significant  part  of  the  files  of  the  research 
worker  who  uses  the  camera.  The  writer's  collection  of  several  hun- 
dred cartoons,  gathered  from  every  section  of  the  country  at  small 
reproduction  expense,  interpret  the  local  attitude  on  economic  and 
financial  questions  in  the  period  of  the  eighties  and  nineties  more 
poignantly,  perhaps,  than  any  other  one  possible  type  of  source  ma- 

Obtaining  Complete  Historical  Record  Pictures 

But  maps,  charts,  graphs,  and  cartoons  do  not  complete  the  list 
of  new  sources  made  readily  accessible.  Highway  signs,  terrains, 
badges,  handbills,  broadsides,  uniforms,  machinery  and  implements, 
deserted  villages,  abandoned  mining  camps,  relies,  ancient,  medieval, 
and  modern  inscriptions,  and  even  flora  and  fauna,  are  readily  and 
accurately  recorded  by  Leica  miniature  photography.  Whatever  the 
eye  can  perceive  as  source  material,  the  camera  can  record  and 
preserve.  My  own  files  on  the  great  depression  of  1929  may  in  future 
years  prove  richer  because  of  their  inclusion  of  photographs  of  silent 
factories,  of  bread  lines,  of  the  unfortunates  seeking  warmth  and  a 
place  to  rest  in  the  St.  Louis  Public  Library,  of  the  bonus  marchers, 
of  men  and  boys  tramping  the  highways  and  riding  the  transconti- 
nental freights  looking  for  work,  and  of  many  other  evidences  of 
economic  turmoil.  The  New  Deal  may  prove  more  interesting  because 
of  a  photographic  record  of  the  inauguration,  of  closed  banks,  of 
farmers  plowing  under  cotton,  and  of  emergency  workers  on  govern- 
ment payrolls. 

There  are  other  advantages.  The  research  worker  often  finds  the 
amount  of  time  that  he  can  spend  at  a  given  place  limited.  The 
camera  prolongs  his  stay  in  effect  by  enabling  him  to  accomplish 
more  than  he  can  by  any  other  method  of  copying;  it  also  permits 
him  to  bring  exact  reproductions  of  the  original  documents  to  the 
quiet  of  his  own  study  for  careful  analysis  and.  interpretation.  This 
is  particularly  important  where  translation  is  necessary.  The  scholar 
who  works  in  European  archives  on  a  summer's  journey  has  not  the 
time  (and  often  not  the  money)  to  spend  hours  puzzling  over  a 
manuscript  the  chief  difficulty  of  which  is  translation,  when  he  may 
project  the  writing  in  an  enlarged  form  on  a  wall  or  screen  in  his 
own  home. 

A  university  friend  whose  time  for  traveling  was  extremely 
limited  recently  photographed  enough  of  the  literature  of  the  Penn- 
sylvania Dutch  in  a  few  weeks  to  employ  all  his  study  hours  for  a 
year.  Transcription  too  sometimes  presents  problems.  The  writer 


discovered  a  particularly  valuable  diary  in  Kansas;  unfortunately, 
it  was  written  in  a  system  of  shorthand  with  which  he  was  not 
familiar.  Its  value  was  attested  by  the  convenient  fact  that  many 
pages  had  been  partially  transcribed.  The  diary  was  photographed 
quickly  and  cheaply  and  later  consultations  with  expert  stenographers 
resulted  in  its  complete  transcription. 
The  Kesearch  Equipment 

The  entire  camera  outfit  for  traveling  research  is  little  bulkier 
than  a  typewriter.  I  recently  completed  a  twelve-months  research 
trip  through  the  West  and  the  South  in  which  I  collected  more  than 
twenty  thousand  copies  of  manuscripts.  My  equipment  consisted  of 
a  Leiea  camera,  Fuldy  Copy  Attachment,  baseboard,  upright  and 
sliding  arms,  two  extension  tubes,  and  two  ordinary  goose-neck  lamps 
fitted  with  one-hundred  watt  bulbs.  It  is  well  to  carry  also  a  develop- 
ing tank  and  some  standard  prepared  developer.  Films  may  easily 
be  developed  each  night  and  carefully  checked  for  omissions.  This 
cheeking  is  made  reasonably  simple  in  my  own  ease  by  the  fact  that 
I  keep  a  careful  index  of  every  photograph,  recording  the  date,  place, 
person,  subject,  and  collection  or  library  from  which  the  material  is 
obtained.  The  collection  and  library  as  well  as  an  identifying  num- 
ber are  easily  photographed  with  each  manuscript.  Identification 
and  number  may  be  on  a  simple  typed  slip  or  a  regular  holder 
with  movable  letters  and  figures.  The  size  of  the  original  may  be 
shown  by  established  measuring  marks  on  the  baseboard.  Each  roll  of 
film  also  is  identified  by  a  number,  photographed  at  the  beginning  and 
the  end. 

A  scientific  knowledge  of  photography  is  not  necessary  in  order 
to  use  the  camera  as  a  research  instrument.  Careful  observation  of 
results  and  some  idea  of  the  fundamentals  of  lights  and  shadows  are 
helpful.  The  research  worker  is  primarily  interested  in  obtaining 
the  best  possible  photographs  in  the  least  possible  time.  He  may  be 
compelled  to  compromise  between  quality  and  quantity.  He  cannot 
spend  too  much  time  on  artistry.  The  perfect  negative,  however,  is 
worthy  of  attempt  because  of  the  possibility  of  enlarging  it  for  future 
use  as  illustrative  book  material.  For  the  beginning  photographer 
of  ordinary  manuscripts  the  two  fundamental  things  to  remember 
are:  first,  keep  lights  as  uniform  as  possible  over  the  field  to  be 
photographed;  and  second,  be  sure  that  the  camera  is  in  focus,  The 
£oose-neck  desk  lamps  are  conveniently  carried,  but  care  must  be 
exercised  in  placing  them.  Turn  the  shades  so  that  the  rays  cross 
over  the  manuscript.  A  magnifying  glass  is  helpful  in  focusing,  par- 


Historical  Research 

ticularly  on  newspapers.  The  perfectly  focused  negative,  regardless 
of  the  size  of  the  manuscript  photographed,  is  easily  read. 

The  length  of  exposure  in  copying  varies  with  the  intensity  of 
the  light  used,  the  size  of  the  diaphragm  opening,  the  color  of  the 
paper  which  is  being  photographed,  and  the  nature  of  the  film  em- 
ployed. Practice  alone  can  establish  the  best  exposure  for  any  par- 
ticular equipment.  The  use  of  a  dependable  exposure  meter  is  highly 
recommended.  The  f  :9  diaphragm  opening  has  proved  the  best  in 
my  own  work.  It  is  small  enough  to  give  clear-cut  lines  in  the  photo- 
graph, and  yet  it  permits  enough  light  to  ascertain  whether  the 
manuscript  is  in  proper  condition,  when  iising  the  Fuldy  attachment, 
without  opening  the  diaphragm  with  each  exposure.  Where  single 
sheets  of  paper  of  somewhat  uniform  size  are  being*  photographed, 
there  is  no  need  for  repeated  focusing. 

The  cheapest  and  perhaps  best  general  film  for  ordinary  repro- 
duction seems  to  be  the  regular  positive  stock.  This  film  with  the 
f  :9  opening  and  two  one-hundred-watt  bulbs  photographs  black  and 
white  papers  at  an  exposure  of  about  one  second;  yellowed  newspapers 
may  run  to  three  seconds.  Allowances  must  be  made  for  the  difference 
in  intensity  between  direct  and  alternating  current  lights,  and  also 
for  extremely  bright  days.  Filters  are  valuable,  but  longer  exposures- 
must  be  made  when  they  are  employed.  Panchromatic  film  such  as 
Du  Pont  Micropan  should  be  used  and  especial  care  taken  in  copying 
graphs,  charts,  and  cartoons  which  are  intended  for  illustrations  in 




"STONEWALL^    AND    FROM     HEfiE    8E- 




Fig.  204     Highway   Signs   which   Give   Historical   Information    Should  be 
Photographed.    Photos  by  W.  D.  Morgan  and  James  A.  Barnes 


The  most  economical  method  of  buying  film  is  in  bulk;  the  two  hun- 
dred-foot lengths  have  many  advantages.  The  traveling  research  worker, 
however,  must  learn  to  load  both  his  cartridges  and  his  developing  tank  in 
darkness.  Bathrooms  and  closets  are  most  frequently  pressed  into  service 
as  darkrooms,  and  one  often  finds  that  there  is  no  place  for  attaching  the 
safety  lamp.  A  little  practice  makes  it  possible  to  load  in  complete  darkness 
almost  as  quickly  as  with  a  lamp.  An  infallible  test  for  determining  the 
emulsion  side  of  the  film  is  to  touch  it  to  the  tongue  because  the  tongue 
sticks  to  the  emulsion.  Practice  and  observation,  while  they  may  not  make 
of  the  researcher  an  expert  photographer,  will  soon  lead  to  qualifications 
sufficient  for  his  work. 

The  student  may  use  his  material  in  two  ways:  either  make  enlarge- 
ments on  regular  photographic  paper,  or  else  use  a  projector.  For  concen- 
trated study  enlargements  on  paper  are  preferred.  Projection  of  the  nega- 
tive film  itself  of  that  material  which  is  to  be  used  only  a  few  times  is  thor- 
oughly satisfactory.  The  total  cost  per  page  when  used  in  this  manner  is 
only  a  fraction  of  a  cent.  If  repeated  projections  are  to  be  made,  it  is  safest 
to  make  them  from  positive  prints.  By  carefully  reading  the  special  chap- 
ters on  developing,  copying,  making  positives,  and  projecting,  a  thorough 
understanding  of  this  subject  may  be  acquired. 

The  photographic  method  of  research  is  certainly  more  econom- 
ical and  much  more  rapid  than  any  other  employed;  it  is  also  far 
more  accurate.  On  a  research  trip  of  more  than  fifteen  thousand 
miles  the  writer  found  no  objections  to  the  use  of  the  camera.  Own- 
ers of  manuscripts  and  documents  are  easily  convinced  that  misinter- 
pretation and  misquotation  are  less  likely  to  occur  when  the  material 
is  photographed  than  when  copied  by  hand  or  typewriter. 

This  Enlarging,  Reading,  and  Pro- 
jection Outfit,  known  as  the  Vokom, 
can  be  used  for  Examining  Nega- 
tives or  Positives.  A  small  Mirror 
is  attached  for  throwing  the  Image 
upon  a  Projection  Screen.  Note 
Ventilating  Ring  around  Lamp 
Housing  for  use  with  Higher  Power 




For  the  copying  I  do  in  iny  study  the  camera  is  mounted  on  the 
Leiea  arm  which  slips  over  a  4-foot  upright  fastened  to  the  table. 
On  the  table  beneath  the  camera  concentric  rectangles  are  drawn, 
corresponding  to  the  sizes  given  in  the  Leica  tables  for  use  with  the 
front  lens.  Along  the  top  line  of  each  rectangle  there  is  written 
the  helical  focus  to  be  used  for  copying  that  size,  the  distance  of 
the  camera  from  the  object,  and  the  amount  of  reduction.  There 
are  five  of  these  rectangles,  from  8  x  12  to  13  x  19  inches.  A  plumb 
bob  dropped  to  the  center  serves  as  a  check  on  the  position  of  the 
camera.  Very  satisfactory  results  may  be  obtained  in  focusing  by 
measurement  with  this  arrangement,  and  it  is  more  convenient  than 
the  copy  attachment  excepting  in  copying  material  that  varies  greatly 
in  size. 

If  the  camera  is  moved  from  its  original  position  on  the  Sliding 
Arm  to  the  Sliding  Focusing  Copy  Attachment,  the  lens  position  is 
moved  to  one  side  and  the  field  no  longer  corresponds  to  the  rectangles 
as  drawn  on  the  table.  (In  the  Fuldy  Copy  Attachment  that  I  use  the 
center  is  2  inches  to  the  left  of  the  original  center,  when  the  Leica  is 
attached  directly  to  the  Sliding  Arm.) 

It  is  necessary  to  use  a  supplementary  lens  or  an  extension  tube  to 
focus  by  measurement.  If  the  various  extension  tubes  are  to  be  used 
between  the  Leica  and  the  lens  the  supplementary  lenses  are  not 
required.  In  this  latter  case  use  the  tables  given  in  the  chapter  on 
copying.  In  case  a  definite  checkup  is  required  the  single  exposure 
Leica  is  of  value  for  securing  exact  focus  for  the  various  extension 
tubes,  as  well  as  the  different  positions  of  the  Leica  lenses. 

I  have  found  that  the  f  :3.5  lens  plus  the  front  lens  No.  1  meets 
all  ordinary  needs  in  copying.  It  is  a  good  lens  combination  for 
general  work.  However,  where  the  type  of  material  to  be  copied 
varies  from  such  small  objects  as  postage  stamps  up  to  newspaper-size 
pages,  it  would  be  convenient  to  have  an  additional  lens  or  use  the 
ground  glass  copy  attachment.  The  smaller  apertures  give  better 


definition,  and  it  is  a  good  plan  to  make  stop  f  :12.5  or  f  :18  the  usual 
aperture  in  copying.  It  is  possible,  however,  to  make  legible  copies 
with  as  wide  an  aperture  as  f  :6.3  and  this  of  course  speeds  up  the 
exposures.  The  character  of  the  material  to  be  copied  must  be  taken 
into  account  in  judging  the  limits  within  which  the  aperture  may  be 
opened.  Since  the  smaller  aperture  means  greater  depth  of  focus,  it  is 
not  necessary  to  re-focus  even  in  copying  very  thick  volumes,  when 
the  lens  is  stopped  to  f  :18. 

The  Model  F  or  G  Leica  (with  focal  plane  shutter)  make  double 
exposures  impossible  and  are  probably  the  most  satisfactory  models  to 
use  in  copying.  Earlier  models  can  be  adapted  by  the  use  of  a  slow 
exposure  timer.  If  enough  light  is  used  to  reduce  exposures  to  one 
or  one-half  second,  there  will  very  likely  be  considerable  variation  in 
density  unless  the  exposures  are  automatically  timed. 

The  Model  FF  camera  may  be  used  in  long  copying  jobs,  because 
of  its  greater  capacity  of  film. 

With  the  standard  camera  a  half-dozen  or  more  magazines  may 
be  loaded  in  the  morning  and  reloaded  in  the  changing  bag  if  they 
are  all  exposed  in  the  course  of  the  day.  (I  keep  a  can  in  the 
changing  bag  supplied  with  film  cut  in  advance  into  5  foot  strips.) 
This  is  very  satisfactory  for  occasional  copying,  but  in  continuous 
work  loading  the  magazines  and  changing  them  in  the  camera  takes 

I  O  ,\  O  U 

PJ  rorcdl  afl<J  arc  to  be  fold  by  f.  C«^  I 

Prwwr  to  tlic  wid  Company  i  *  *  5 

Fig.  205  Title  Page  Showing- 
the  Lists  of  Deaths  from  the 
London  Plague  of  1665.  Photo 
by  F.  G.  Ludwig,  Yale  Library 


Copying  MSS 

up  a  disproportionate  amount  of  time.    There  are,  however,  compar- 
able disadvantages  with  long  rolls. 

The  Eastman  or  Du  Pont  process  or  positive  safety  films,  bought 
in  200  or  400  foot  rolls,  are  satisfactory  for  copying  any  black  and 
white  material.  This  safety  film  gives  good  contrast,  and  can  be  pro- 
cessed in  a  dark  room  with  yellow  light,  a  considerable  convenience  for 
the  inexperienced  worker.  In  copying  colored  material  the  panchro- 
matic emulsions  may  be  used.  A  document  mimeographed  in  violet  ink 
came  out  very  badly  on  the  positive  film,  but  gave  an  excellent  copy 
on  Du  Pont  Micropan.  Dr.  Bendikson  of  the  Huntington  Library  has 
published  a  number  of  articles  (Library  Journal,  Oct.  1,  1932,  Sept. 
.15,  1933,  etc.)  describing  his  methods  and  results  in  copying  colored, 
faded,  blotted  and  charred  documents. 

In  copying  material  printed  on  thin  paper  it  is  necessary  to  inter- 
leave with  white,  to  prevent  the  page  underneath  from  showing 
through.  Where  the  ink  on  one  side  of  the  page  shows  through  on 
the  reverse  side  I  interleave  with  black,  as  this  reduces  the  contrast 
and  may  eliminate  the  show-through  on  the  negative. 

Spring  clips  and  rubber  band's  may  be  used  to  hold  the  paper  flat  in 
copying,  or  a  piece  of  plate  glass  may  be  placed  over  the  object.  Glass  is 
troublesome  to  use  as  it  must  be  watched  carefully  for  reflection  and  flare. 
In  a  library  where  the  equipment  is  available  the  camera  may  be  mounted 
on  the  photostat  machine,  so  that  the  photostat  copy  holder  and  illumination 
can  be  utilized. 

Two  desk  lamps  with  100-watt  bulbs  give  adequate  illumination  for 
copying,  with  a  slow  exposure.  They  may  be  placed  one  on  each  side  of  the 
object,  the  lamp  placed  18  inches  above  the  outer  edge.  This  is  not  a  perfect 
lighting  system,  as  there  is  a  variation  with  the  size  of  the  page  copied. 
This  variation  however  does  not  visibly  affect  the  density  of  the  negative 
(or  length  of  exposure)  in  copying  up  to  folio  size  pages.  When  newspaper- 
size  pages  are  copied  it  becomes  necessary  to  use  two  lights  at  each  side. 
Care  must  be  taken  to  avoid  a  flare  spot  on  the  curve  of  the  page  in  copying 
bound  material.  When  the  paper  has  a  glossy  finish,  tissue  paper  hung 
over  the  lights  will  increase  diffusion. 

With  two  100-watt  lights,  placed  as  described,  and  an  aperture  of  f  :18 
the  exposure  will  be  between  4  and  6  seconds  on  process  film.  Two  seconds 
will  result  in  a  negative  too  light  to  be  read  easily  in  the  projector,  8  sec- 
onds will  be  too  dense.  By  substituting  Photofloods  for  the  100-watt  lamps, 
the  exposure  can  be  reduced  to  one  second,  and  by  enlarging  the  aperture  it 
is  possible  to  copy  with  an  exposure  of  l/20th  second.  There  is  no  appre- 
ciable decrease  in  contrast  with  the  use  of  photofloods,  or  with  the  use  of 
Cooper  Hewitt  lights. 

Since  the  time  necessary  to  turn  pages  and  arrange  the  document  is 
always  longer  than  the  actual  exposure,  there  is  usually  no  advantage  to 
be  gained  in  working  close  to  the  limit  of  good  definition  with  a  wide 


The  small  tank  may  be  used  for  occasional  films,  but  for  developing  a 
number  of  strips,  the  most  satisfactory  method  seems  to  be  simply  to  stand 
the  film  on  edge  in  a  deep  tray,  drawing  it  out  to  prevent  adhesion  in  curling 
Several  strips  may  be  handled'  at  once  in  this  manner  and  with  an  assistant 
present  to  hand  the  strips  a  large  quantity  of  film  may  be  developed 
within  a  short  time,  without  any  equipment  except  the  tray.  Where  ex- 
posures are  as  standardized  as  they  are  in  copying  there  is  no  great  need 
for  developing  by  inspection.  In  copying  printed  and  written  materials,  the 
beginner  must  not  forget  that  he  is  aiming  at  contrast  rather  than  the 
soft  tones  sought  in  pictorial  work.  Emphasis  in  developing  should  be  on 
securing  contrast.  There  is  little  difficulty  in  obtaining  adequately  fine 
grain  results  with  the  process  films. 

Extreme  care  is  necessary  to  avoid  scratches  and  spots  since  they  may 
obliterate  essential  words  or  letters  of  the  document  copied.  The  film  should 
be  touched  only  on  the  edge,  and  should  not  be  allowed  to  drag  across  the 
side  or  bottom  of  a  tray,  where  sediment  may  scratch  it.  Chamois  used  in 
wiping  the  film  before  drying  should  be  free  from  grit. 

Where  negatives  are  valuable  it  is  a  good  plan  to  give  them  a 
second  bath  in  fresh  hypo  and  a  double  period  of  washing  to  insure 

As  soon  as  they  are  well  dried  the  film  strips  should  be  rounded 
at  the  ends  and  placed  in  the  containers.  It  is  said  to  be  advisable  to 
roll  the  film  with  the  emulsion  side  out. 

The  need  for  cleanliness  in  the  dark  room  is  frequently  men- 
tioned and  should  be  called  most  emphatically  to  the  attention  of  those 
whose  darkroom,  as  is  often  the  case  with  amateurs,  is  in  the  basement 
or  the  attic,  where  there  is  apt  to  be  a  good  deal  of  dust.  Film  that 
is  allowed  to  become  dusty  soon  becomes  scratched.  It  should  not 
be  dried  in  a  room  where  spilled  hypo  has  dried  and  crystallized. 
The  amateur  engaged  in  copying  will  produce  a  much  greater  bulk 
of  film  negatives  than  would  likely  be  produced  in  pictorial  work, 
and  it  is  therefore  necessary  to  care  for  a  considerable  number  of 
strips  if  processing  is  done  at  home. 

Making  and  Using  Film  Copies  .  .  . 
The  Clerical  Side 

A  system  of  filing  and  identifying  negatives  is  an  important 
factor  in  putting  a  collection  of  film  copies  to  the  best  account.  Most 
of  us  follow  the  line  of  least  resistance  and  if  there  is  a  good  deal 
of  bother  about  unwinding  film  and  searching  for  the  piece  wanted 
we  are  inclined  to  neglect  the  film  copies,  no  matter  how  excellent 
the  photography  may  have  been.  The  following  plan  fits  my  own 
needs  and  might  be  adapted  to  the  use  of  others. 

The  film  strips  are  numbered  and  filed  under  headings  that 
parallel  those  in  a  general  file  of  notes  and  documentary  material. 


Copying  MSS 

Crumbling  of  Newspaper  Files 
Declared  Loss  to  Historians 

"By  The  Associated  Press. 

.  MINNEAPOLIS,  Dec,  28.— "Tons 
of  history"  are  being  swept  tip 
daily  from  the  floors  of  American 
libraries  because  of  the  absence  of 
art  economical  preservative  to  pre- 
vent ruin  of  n^wspap^r  files,,  the 
American  Council  of  Learned  So- 
cieties was  told  here  today. 

'  Wood  pulp  paper,  with  which 
most  of  the  presses  are  fed,  serves 
the  historian  badly  because  it 
cracks,  tears  and  crumbles,  threat- 
ening destruction  of  a  primary 
source  of  material  for  future  in- 
terpreters of  modern  life,  Dr,  Solon 
JV  Buck  of  the  University  of  Pitta- 
burgh  said, 

He  suggested  that  cameras  capa- 
ble of  reducing  facsimiles  of  news- 
paper pages  to  small  size  requiring 
little  space  in  archives  might  solve 
the  .problem  in  part  but  that  a  low- 
cost*  adequate  preservation  which 
would. insure  the  safety  of  original 
files  was  the  greatest  need. 

Fig.  206  Newspaper  Clipping 
Warns  Against  the  Loss  of 
Valuable  Records 

Fig.  207      Cover  of  an  Early  Medical 
Book  Copied  for  Later  Study 

A  record  of  the  material  copied  is  photographed  in  each  case  and 
becomes  part  of  the  negative,  serving  as  a  label. 

The  first  exposure  on  each  strip  of  film  copies  a  large  number 
that  can  be  read  on  the  negative  without  a  lens,  and  a  good  deal  of 
eye  strain  is  avoided  in  identifying  film  strips  by  this  large  number 
at  one  end.  The  numbered  series  serves  as  a  check  against  the  loss 
of  film  in  process  or  in  use. 

The  second  exposure  copies  a  label,  which  contains  the  following 
information : 

a.  title  of  document 

b.  filing  designation 

c.  photographic  conditions 

d.  number  of  pages  copied 

It  is  not  necessary  to  use  an  entire  frame  for  this  label,  as  it 
may  be  placed  alongside  a  title  page  and  photographed  in  that  posi- 
tion. After  the  entire  strip  of  film  has  been  exposed,  the  number  of 
pages  copied  may  be  noted  on  the  original  label,  and  if  the  document 


has  not  been  completed  the  label  may  be  carried  forward  to  the  next 
film  strip.  The  original  label  is  eventually  filed  in  the  general  file, 
with  other  notes,  and  serves  as  a  cross  reference  to  the  film.  In 
special  cases,  as  in  copying  a  series  of  documents,  it  is  convenient 
to  keep  a  list  of  the  contents  of  the  film  strips,  taken  from  the  labels 
before  they  are  filed. 

The  entry  on  photographic  conditions  may  be  referred  to  in  comparing 
the  results  of  various  methods  of  copying,  and  also  in  planning  retakes 
where  the  copying  has  not  been  successful.  If  a  large  amount  of  material 
has  been  copied  in  the  course  of  travel,  a  note  on  the  label  of  the  condition 
of  the  document,  color  of  ink  and  paper,  and  the  exposure  given,  will  explain 
the  results  in  the  case  of  a  poor  negative  and  may  be  taken  into  account  in 
ordering  retakes.  If  missing  pages  or  other  variations  in  the  document  are 
noted  on  the  label  it  will  save  turning  again  to  the  original  in  checking- 
over  the  film  negatives. 

It  is  a  good  plan  to  number  the  exposures  or  frames  in  copying.  Small 
cardboard  squares  which  stay  in  place  when  dropped  at  the  corner  of  the 
page  are  desirable  (mine  are  hat  check  numbers).  These  frame  numbers 
are  used  in  collating  enlargements  or  in  giving  orders  for  enlargements  to 
be  selected  from  a  film  strip.  A  running  title,  typed  on  a  narrow  piece  of 
heavy  paper  and  placed  at  the  bottom  of  each  page,  is  also  useful  in  identi- 
fying enlargements  and  in  identifying  pages  as  they  are  read  in  the  pro- 

To  add  the  frame  number  and  running  title,  interleave  pages  to  prevent 
show-through,  and  attach  spring  clips  to  hold  the  pages  flat, — all  occupies 
about  twice  as  much  time  as  the  actual  exposure  in  copying.  In  my  experi- 
ence, however,  the  time  is  saved  twice  over  in  the  future  use  of  the  negatives. 
To  assort  the  enlargements  from  a  number  of  film  strips,  if  they  are  not 
numbered,  will  sometimes  take  as  much  time  as  the  photographic  process 
itself.  On  one  occasion,  before  I  adopted  the  numbering  system,  I  had 
copied  several  slightly  varying  drafts  of  a  single  document,  had  75  enlarge- 
ments made,  and  found  it  was  necessary  to  compare  each  enlargement  with 
the  original  in  order  to  be  sure  the  pages  were  arranged  in  correct  sequence. 
It  took  as  much  time  as  a  jig  saw  puzzle. 

An  advantage  of  the  film  copy  method  is  that  proofreading  is 
riot  required.  It  is  necessary,  however,  to  look  over  the  film,  with  a 
lens,  first  to  see  that  it  is  satisfactory  from  the  photographic  poini 
of  view,  and  then  to  discover  if  what  we  might  call  clerical  errors 
have  occurred. 

Copying  Mistakes  and  Their  Remedy 

Faults  in  photography  most  likely  to  be  encountered  are,  first, 
those  in  exposing,  such  as  errors  in  focusing,  the  object  not  being  in 
the  center  of  the  field,  over  or  under  exposure,  spots  caused  by  im- 
proper illumination  or  by  reflection  from  bright  objects  near  the  page 
copied,  and  the  like.  Second  are  the  accidents  in  processing,  such  as 
scratches,  pin  holes  and  water  spots,  and  over  or  under  developing. 


Copying  MSS 

The  most  likely  clerical  errors  are  mislabeling  of  documents,  or 
skipping  pages.  The  following  device  serves  as  a  check  on  missing 
pages,  so  that  it  is  not  ordinarily  necessary  to  check  them  on  the 
finished  negative. 

I  connt  thirty  pages  in  the  document  and  place  a  marker  at  the 
end.  If  the  camera  counter,  the  frame  numbers,  and  the  marker  in 
the  document  coincide  at  the  end  of  the  strip,  it  is  reasonably  certain 
that  no  pages  were  omitted.  If  an  error  has  been  made  the  best  way 
to  correct  it  usually  is  to  retake  the  whole  strip.  This  avoids  isolated 
pages,  taken  at  a  later  time,  which  must  be  spliced  on  to  the  film  strip. 

Film  Storage 

I  keep  the  Leica  film  strips  in  small  tins,  labeled  on  the  top.  These  can 
be  arranged  in  rows  in  a  shallow  drawer  and  treated,  so  far  as  filing  is 
concerned,  as  if  they  were  folders  in  an  ordinary  vertical  file.  The  label 
on  the  tin  corresponds  to  the  file  designation  photographed  on  the  film  and 
also,  of  course,  to  the  headings  in  my  general  file. 

Where  there  are  a  number  of  short  takes  on  a  strip,  I  cut  them  apart, 
disregarding  the  strip  number,  and  file  the  short  slides  with  other  material 
in  the  general  file.  Paper  folded  and  pasted  on  the  back  of  a  folder  forms 
pockets  to  hold  the  film. 

The  best  advice  on  storage  that  I  have  been  able  to  obtain  indi- 
cates that  proper  processing  is  the  prime  condition  of  film  per- 
manence. There  is  apparently  no  great  danger  of  loss  if  the  film  is 
kept  in  a  reasonably  cool  place.  Since  almost  all  my  film  is  on  the 
acetate  base  there  is  no  more  fire  danger  involved  in  keeping  It  thau 
in  keeping  papers  of  any  sort. 

Reading  the  Negatives 

After  the  copies  are  made  and  filed  in  some  safe  and  easily  accessible 
manner,  the  problems  involved  in  using  them  are  relatively  simple.  The 
film  may  be  used  in  short  or  long  strips,  on  reels,  or  the  frames  may  be  cut 
apart  and  mounted  individually  in  cards,  to  be  used  as  slides.  When  suit- 
able reading  devices  are  available  the  film  may  be  projected  to  a  convenient 
size  and  read  at  close  range  in  a  light  room,  so  that  a  typewriter  may  be 
used  in  making  notes.  If  the  projector  used  will  not  allow  a  light  at  the 
desk,  it  is  still  possible  to  record  notes  on  a  dictaphone  as  the  film  is 

When  enlargements  are  desired,  they  may  be  greatly  reduced  or  made 
as  large  as  required.  Copies  of  newspaper  clippings,  for  example,  may  be 
enlarged  to  twice  the  original  size,  or  on  the  other  hand  a  series  of  letters 
may  be  reproduced  to  fit  a  3  x  5  card  file.  Such  papers  as  Photostat  R, 
Insurance  Bromide,  and  Haloid  Record  are  satisfactory  for  enlargements. 

If  a  few  frames  are  to  be  selected  for  enlargement  from  a  long  strip 
of  film,  the  enlargements  may  be  indicated  by  the  frame  number  or  by 
short  pieces  of  string  tied  into  the  perforations. 

In  planning  for  enlargements  in  large  quantity,  it  must  be  taken  into 
account  that  they  add  a  large  sum  to  the  very  low  cost  of  the  film  copy,  as 


well  as  increasing  the  bulk  of  material  to  be  stored.  To  the  cost  of  making 
the  enlargements  should  also  be  added  a  charge  for  clerical  work  in  assort- 
ing and  checking  over  the  finished  copies.  It  may  also  be  decided  to  mount 
the  enlargements,  to  get  away  from  the  tendency  of  the  paper  to  curl,  and 
this  adds  another  charge.  If  a  suitable  projector  is  available  the  beginner 
in  the  field  of  film  copy  ought  by  all  means  to  give  a  fair  trial  to  reading 
the  film  by  projection  before  deciding  out  of  hand  that  all  his  film  copies 
must  be  enlarged. 

Tiger  Beetle 

J.  M.  Leonard 






The  photographer  who  is  weary  of  portraits  and  pictorials  or 
who  is  bored  by  the  discussions  of  purist  versus  creative  may  take 
new  hope.  If  he  wishes  to  combine  amusement  and  education  with 
a  host  of  interesting  photographic  problems,  he  should  explore  the 
world  of  miniature  monsters  which  awaits  him  in  his  own  backyard. 
He  will  find  a  life  as  fascinating  and  as  bizarre  as  any  that  ever 
roamed  the  hot  sands  and  the  reeking  swamps  of  prehistoric  times. 

Such  an  exploration,  through  the  eye  of  the  camera,  will  reveal 
creatures  clothed  in  bone,  in  feathers,  and  in  hair;  creatures  with 
from  two  to  eight  eyes,  and  from  one  to  nearly  thirty  thousand  lenses 
or  facets  to  each  eye;  creatures  so  weird  in  appearance  that  they  seem 
to  belong  to  another  age.  These  are  the  insects  and  the  spiders. 
Their  variety  of  form  is  boundless  and  in  brilliancy  of  color  they 
equal  if  not  surpass  the  most  gorgeous  flowers.  Their  habits  and 
their  social  conduct  are  of  such  absorbing  interest  that  the  insect 
photographer  need  not  feel  surprised  should  he  suddenly  find  himself 
more  interested  in  studying  the  actions  of  the  insects  than  in  pho- 
tographing them. 


Entomologists  estimate  that  there  are  a  half  million  or  more 
known  species  of  insects.  They  constitute  by  far  the  largest  group 
of  Hying  creatures  and  greatly  exceed  the  combined  total  of  all  others 
on  the  earth,  in  the  air,  and  under  the  water.  Doctor  Frank  E. 
Lutz  of  the  American  Museum  of  Natural  History  states  that  there 
are  approximately  fifteen  thousand  species  of  insects  to  be  found  with- 
in fifty  miles  of  New  York  City,  and  nearly  eleven  thousand  species 
within  the  state  of  New  Jersey,  and  these,  bear  in  mind,  are  species 
and  not  individuals.  The  photographer  who  takes  up  this  branch  of 
work  will  never  lack  subjects.  Also  he  will  have  a  year  around  hobby, 
for  the  insects  may  be  photographed  alive  in  the  field  or  may  be 
mounted  and  saved  for  the  long  winter  evenings. 

Catching  the  Insects 

Although  insects  are  so  numerous  and  so  widely  distributed  a 
few  hints  as  to  where  to  look  and  what  to  look  for  might  be  helpful. 
The  collector  doubtless  needs  no  suggestions  as  to  where  to  find  such 
household  insects  as  the  roach,  silver  fish,  clothes  moth,  house  fly  and 
mosquito.  These,  however,  constitute  a  very  small  percentage  of  the 
thousands  of  varieties  which  lie  beyond  the  screens  and  the  front 

Pig.  208    Head  of  Wolf  Spider          Pig.  209     Head  of  Jumping  Spider 
Note  How  Eye  Arrangement  Differs 


Miniature  Monsters 


Fig.  210     The  Northern  Centipede  which  Lives  in  Houses 

While  many  insects  are  much  in  evidence  some  of  the  most  in- 
teresting ones  prefer  seclusion  and  their  society  must  be  sought. 
Turning  over  an  old  board  or  a  rock  in  a  field  may  admit  one  to  the 
private  lives  of  a  few  crickets,  a  family  of  sow  bugs,  or  a  miscellane- 
ous collection  of  beetles.  Other  insects  will  be  found  under  bark,  in 
rotten  wood,  in  flowers,  among  the  roots  of  plants,  and  in  fact  prac- 
tically everywhere  that  the  careful  collector  cares  to  look.  The  chief 
requisites  of  a  collector  are  active  curiosity,  quick  fingers,  and  nimble 
legs.  For  the  capture  of  moths,  butterflies,  dragon  flies,  or  other 
flying  insects  a  net  is  essential.  This  may  be  purchased  for  a  rea- 
sonable price  from  any  dealer  in  entomological  equipment. 

While  all  insects  are  interesting  photographically,  there  are  a 
few  of  the  common  ones  which,  because  of  certain  outstanding  points 
of  interest,  should  appeal  to  the  beginner  in  insect  photography. 
The  spiders — which  by  the  way  are  not  insects  but  are  of  the  class 
Araclmida,  order  Araneida — are  interesting  because  of  their  ferocious 
appearance  and  the  number  and  arrangement  of  their  eyes  (figs.  208 
and  209).  The  normal  number  of  eyes  is  eight  and  all  of  the  eyes  are 
simple :  in  none  of  them  is  the  outer  layer  divided  into  facets  as  in  the 
compound  eyes  of  insects.  The  normal  arrangement  is  regarded  as 
two  rows,  each  containing  four  eyes,  but  they  may  be  found  in  three 
and  even  four  rows.  Grasshoppers  are  interesting  because  of  their 
smug  expressions  (fig.  211).  Scutigera  Forceps,  the  northern  centi- 
pede which  lives  in.  houses,  appears  like  a  "bleached  carcass  on  the 
desert  when  photographed  on  sand  against  a  black  background  (fig. 


Fig.  211  Grasshopper 

Elmar  135mm  lens,  S.  F. 
Attachment,  60mm  ext. 
tube,  36  seconds,  at  f:18, 
DuPont  Superior  Film 

210.    The  larvae  of  many  of  the  large  moths  such  as  Cecropia,  Prom- 
ethia,  and  Cynthia  look  like  prehistoric  dragons  in  the  photographic 
enlargements.    The  points  of  interest  are  endless  but  the  experimenter 
will  soon  find  his  own  favorites. 
The  Camera  Equipment 

The  camera  used  in  photographing  insects  must  fulfill  several 
important  requirements  if  the  best  results  are  to  be  secured.  Ground 
glass  focusing  is  essential  because  of  the  very  small  depth  of  focus 
which  is  available  when  the  object  to  be  photographed  is  only  an  inch 
or  two  from  the  lens.  The  equipment  selected  should  be  such  that 
the  distance  between  the  lens  and  the  film  may  be  varied  sufficiently 
to  produce  either  photographic  reduction  or  enlargement  of  several 
diameters.  The  range  in  the  size  of  insects  is  such  that  a  fixed 
amount  of  bellows  extension  will  not  serve  for  both  the  large  and 
the  small  ones.  The  image  of  a  praying  mantid  would  have  to  be 
considerably  reduced  before  it  could  be  recorded  on  a  35mm  film, 
whereas  a  mosquito  or  a  fly  would  need  a  corresponding  amount  of 
enlargement  to  bring  out  any  detail. 

The  Leica  camera,  which  is  used  hy  the  writer,  fulfills  all  of  the 
essential  requirements.  The  sliding  focusing  copy  attachment  provides 
ground  glass  focusing,  and  the  lens  extension  tubes  which  are  used  with  it 
permit  a  wide  range  of  photographic  reduction  and  enlargement,  particu- 
larly when  used  with  lenses  of  different  focal  lengths.  As  an  added  ad- 
vantage the  copying-  attachment  and  camera  may  be  mounted  on  a  tripod 
and  used  in  the  field  for  photographing  live  insects.  The  question  of  which 
model  of  the  Leica  to  use  is  significant  only  in  one  respect.  Any  model  is 
satisfactory  but  the  Model  F  has  the  outstanding  advantage  of  including 
speeds  between  1  and  1/20  second,  and  it  is  in  this  range  that  many  of  the 
insect  exposures  will  be  made. 

The  accessory  equipment  for  this  branch  of  work  will  vary  with  the 
ideas  of  the  individual  and  with  the  state  of  his  pocket-book.  A  fairly 
comprehensive  list  is  as  follows: 


Miniature  Monsters 

Sliding1  Focusing  Copy  Attachment  and  Magnifier 
30mm,  60mm  and  90mm  Extension  Tubes 

Elmar  35mm  lens Elmar  or  Summar  50mm  lens 

Lens  Shade Wire  Cable  Release 

Ball  Jointed  Tripod  Head "Triax"  Tripod 

For  field  work  the  50mm  lens  and  the  30mm  tube  generally  will  be 
sufficient.  This  combination  in  connection  with  the  Copy  Attachment  will 
produce  a  .82x  magnification  of  the  image  which  is  about  all  that  can 
be  tolerated  when  working  with  a  live  insect  of  average  size.  If  greater 
magnification  is  used  it  will  be  difficult  to  obtain  critical  focusing  because 
of  the  reduced  depth  of  focus  combined  with  the  need  for  fast  work  when 
photographing  a  live  insect.  The  additional  tubes  and  the  35mm  lens  will 
be  found  useful  for  higher  magnifications  when  the  work  is  done  indoors 
under  controlled  conditions. 

Photographing  in  the  Field 

Photographing  the  insects  in  their  natural  haunts  will  provide 
the  occasion  for  many  a  long  and  interesting  walk.  The  woods,  the 
fields,  and  the  shores  of  ponds  and  streams  are  teeming  with  life.  The 
close  observer  will  find  ceaseless  activity  and  industry  to  an  extent 
unrivalled  among  living  things.  He  will  find  every  trait  and  char- 
acteristic that  can  be  found  in  human  beings  and  many  others  besides. 

For  field  work,  the  equipment  should  include  the  sliding  focus- 
ing copy  attachment  and  magnifier,  a  30mm  tube,  lens  shade,  tripod 
with  ball  jointed  head,  and  wire  cable  release.  In  addition,  a  can 
of  ether  or  carbon  tetrachloride,  a  small  glass  jar  and  a  medicine 
dropper  will  be  found  useful. 

A  little  experience  in  trying  to  photograph  a  live  active  insect 
will  soon  show  the  difficulty  of  doing  so.  Some  insects  are  easily 
frightened  and  others  appear  to  have  a  constant  urge  to  go  some- 
where. Usually  by  the  time  the  camera  is  set  in  place  and  the  some- 
what critical  focusing  has  been  done,  the  insect  has  succumbed  to  this 
urge  and  is  nowhere  to  be  seen.  The  job  will  be  made  much  easier 
and  the  chances  of  a  successful  picture  increased  if  the  insect  is 
placed  under  better  control. 

The  following  method  has  been  used  with  good  results : 

1.  Select  a  twig,  shrub,  rock  or  any  other  place  where  you  would 
like  to  have  the  insect  resting  when  it  is  photographed. 

2.  Focus  the  camera  on  the  particular  spot  selected. 

3.  Next  catch  the  insect  and  place  it  in  the  jar  with  a  few  drops  of 
ether  or  carbon  tetrachloride.    It  should  be  carefully  watched  and 
should  be  removed  from  the  jar  as  soon  as  it  appears  stupefied. 

4.  Place  it  in  the  spot  previously  focused  on,  arrange  its  legs  in  a 
natural  position,  quickly  check  the  focus  and  take  the  picture. 


If  it  has  been  etherized  just  the  right  amount  It  will  be  able  to  cling 

to  the  twig  or  leaf  but  will  not  be  able  to  crawl  or  fly  away  for  a  minute 

or  so. 

Too  much  ether  will  kill  it,  and  too  little  may  enable  it  to  leave  before 

the  picture  is  taken. 

The  insect  may  be  mounted  in  the  field  if  desired  and  thus  kept 
under  more  complete  control.  About  twenty  years  ago  Dr.  David 
Pairchild  of  Washington,  D.  0.,  made  a  number  of  very  interesting 
insect  photographs  which  were  published  in  the  National  Geographic 
Magazine  and  later  in  book  form  as  "The  Book  of  Monsters".  Dr. 
Fairehild  describes  Ms  method  of  mounting  as  follows : 

"Cover  the  top  of  a  small  block  of  wood  with  a  thin,  even  coating  of 
paraffin  or  ordinary  candle  wax  by  letting  the  drippings  of  the  candle  fall 
upon  it.  Pick  a  large  leaf  and  turn  its  upper  surface  down  upon  the  wax, 
before  it  cools,  and  let  it  stick  there;  this  will  give  a  natural  looking  ground 
for  the  insect  to  stand  upon.  Hold  the  insect  over  the  block  of  wood  and 
arrange  the  legs  in  as  natural  a  position  as  you  can  with  a  long  needle  or 
fine  dental  tool.  Then  fasten  each  foot  in  place  by  heating  the  needle  in  the 
candle  flame  and  pricking  a  hole  in  the  leaf  just  under  each  foot  so  that  the 
wax  will  come  up  through  the  leaf  and  hold  it  fast."  The  insect^  is  anes- 
thetized just  before  the  mounting  operation  is  undertaken,  and  is  photo- 
graphed immediately  after  it  is  mounted. 

There  are  times  when  it  pays  to  proceed  with  caution  and  to 
observe  closely  what  the  insect  is  doing  instead  of  immediately  cap- 
turing and  etherizing  it.  An  interesting  series  of  pictures  may  be 
the  reward  of  restraint  and  patience.  The  insect  may  be  engaged 
in  an  operation  which  is  seldom  noticed  and  less  frequently  photo- 
graphed. Careful  scrutiny  may  show  a  cricket  laying  its  egg  through 
a  long  tube  which  has  been  thrust  into  the  earth,  a  jumping  spider 
dancing  before  its  mate  or  a  praying  mantis  depositing  its  egg  mass 
as  shown  in  figure  213. 

The  mantis  series  resulted  from  wondering  why  this  insect  was 
lightly  tapping  the  stick  with  the  end  of  her  body.  It  seemed  to  be 
an  unusual  procedure  and  was  one  which  the  observer  had  not  seen 
before.  After  watching  this  seemingly  futile  performance  for  twenty 
minutes  the  observer  was  rewarded.  The  mantis  began  to  exude  a 
frothy  substance  from  her  body  and  carefully  worked  this  into  place 
on  the  stick.  As  it  was  apparent  that  this  was  the  beginning  of  the 
egg  mass  the  Leica  was  hastily  set  up  and  a  picture  was  snapped. 
Pictures  followed  at  ten  minute  intervals  for  the  two  hours  and 
twenty  minutes  she  required  to  complete  the  operation. 
Selecting  the  Correct  Photographing  Angle 

In  insect  photography,  as  in  any  other  kind,  the  position  of  the 
camera  in  relation  to  the  object  being  photographed  is  an  important 


Miniature  Monsters 

factor  in  determining'  whether  or  not  the  picture  will  be  interesting. 
A  photograph  of  a  man  or  a  horse  taken  from  an  elevation  with  the 
camera  pointing  directly  downward  would  not  be  particularly  pleas- 
ing and  would  give  little  idea  of  what  the  subject  really  looked  like. 
Following  this  line  of  reasoning  best  results  will  be  obtained  if  the 
camera  is  in  the  same  plane  as  the  insect,  or  in  other  words,  at  insect 
level,  although  this  rule  may  be  varied  by  angle  shots  from  slightly 
above  or  below  the  subject.  This  point  is  illustrated  in  figure  212 
which  shows  two  moths,  one  photographed  from  above  and  the  other 
from  the  side. 

It  is  for  the  reasons  given  that  the  "Triax"  tripod  is  suggested  for 
field  work.  It  is  one  of  the  few  that  is  so  constructed  that  the  legs  when 
spread  out  so  that  they  are  in  one  plane,  cannot  be  raised  above  that  plane. 
When  the  tripod  is  placed  on  the  ground  with  the  legs  spread  in  this  manner 
the  camera  will  be  only  a  few  inches  above  the  ground  and  will  be  rig-idly 

The  proper  exposure  time  can  best  be  determined  by  means  of  an  ex- 
posure meter,  bearing  in  mind  that  a  correction  factor  must  be  applied  if 
the  extension  tube  is  used.  Using  the  30  mm.  tube  and  the  50  mm.  lens  set 
at  infinity  with  the  diaphragm  at  f  :6.3  the  exposure  as  determined  by  the 
meter  should  be  multiplied  by  2.2.  It  should  be  remembered  that  when 
an  extension  tube  is  used  between  the  lens  and  the  camera  the  f  values  of 
the  diaphragm  do  not  mean  the  same  as  when  the  lens  is  used  without  the 
tube.  Moving  the  lens  away  from  the  film  increases  the  size  of  the  image 
at  the  plane  of  the  film  and  therefore  a  given  amount  of  light  coming 
through  the  diaphragm  aperture  will  be  spread  more  thinly  over  the  image 
than  would  be  the  case  with  the  lens  in  its  normal  position  in  the  camera. 
This  is  equivalent  to  reducing  the  f  value  and  proportionately  longer  ex- 
posures will  be  required. 

Field  trips  in  search  of  insects  will  disclose  other  interesting 
subjects  for  the  camera.  The  hog-nosed  snake,  the  neighbor's  cat 

Fig.  212     Cecropia  Moth 
Luna  Moth  (right) 


Pig.   213     A  Praying  Mantid 
Depositing  its  Egg  Mass 


Miniature  Monsters 

These     Pictures    were     taken    at    ten-mixmte     in- 
tervals   during    the    two    hours    and    twenty 
minutes    required    to    complete    the     egrg 


and  the  lizard    (fig.  214)    are  among  the  many  trophies  of  such 

Bringing  Home  the  Catch 

If  the  insects  are  to  be  brought  home  to  be  mounted  and  photo- 
graphed at  leisure,  instead  of  being  photographed  in  the  field,  small 
straight  sided  bottles  having  large  mouths  and  screw  caps  will  be 
found  convenient  for  transporting  them.  A  word  of  caution,  how- 
ever, about  properly  segregating  the  occupants  of  the  bottle.  The 
writer,  on  one  of  his  collecting  trips,  found  some  magnificent  speci- 
mens of  huge  black  and  red  ants.  He  captured  a  half  dozen  of  the 
finest  looking  ones  and  placed  them  in  a  small  cardboard  box.  He 
carefully  brought  the  box  home  and  opened  it  to  find  a  grand 
collection  of  spare  parts — legs,  heads  and  bodies  scattered  about. 
In  the  midst  of  the  destruction  was  the  victor — minus  all  six  legs- 
still  waving  avid  mandibles  in  search  of  more  victims.  A  safe  rule 
is  to  have  a  separate  container  for  -each  insect. 

Moths  and  butterflies  should  be  killed  as  soon  as  they  are  cap- 
tured. This  may  be  done  by  carefully  but  firmly  pinching  the  thorax 
between  the  thumb  and  finger.  If  they  are  alive  when  placed  in  the 
container  they  will  thrash  about  and  injure  their  delicate  wings, 

Mounting  the  Insects 

Insects  which  are  to  be  photographed  at  leisure  must  be  per- 
manently mounted.  This  is  a  difficult  job  and,  if  naturalness  is  to 
be  achieved,  calls  for  steady  hands  and  endless  patience.  There 
probably  are  many  ways  of  mounting  and  the  experimenter  may  wish 
to  develop  his  own. 

A  method  which  was  adopted  by  the 
writer  after  many  experiments  is  as 
follows : 

Take  a  piece  of  cardboard  measuring 
about  2x3  inches  for  the  smaller  insects 
and  proportionately  larger  for  those  of 
greater  size.  Cement  to  this  a  piece  of 
Dennis on's  gummed  cloth  mending  tape 
with  the  gummed  side  up.  Place  the  ether- 
ized insect  on  this  and  putting  each  leg  in 
turn  in  the  proper  position,  moisten  the 
gum  around  the  foot  with  a  small  pointed 
stick  which  has  been  dipped  in  water.  The 
events  leading  up  to  and  following  this  op- 
eration are  as  important  as  the  mounting 
operation  itself.  The  live  insect  is  carefully 
studied  until  all  of  the  details  of  one  pose 
are  firmly  pictured  in  the  mind.  This  in- 
Pig.  214  Gila  Monster  eludes  the  position  of  the  antennae  and  of 


Miniature  Monsters 

i  '* '  *"  "i^tewAji*  j 

Fig.  215     A  Praying  Mantid — Showing  one  Method  of  Mounting 

each  of  the  six  legs,  the  angle  of  the  head  and  of  the  body,  and  the  distance 
between  the  under  side  of  the  body  and  the  mounting  surface.  The  insect 
is  then  etherized.  This  may  be  done  by  inverting  a  water  glass  over  it  and 
placing  a  few  drops  of  ether  under  the  edge  of  the  glass  with  a  medicine 
dropper.  Experience  will  show  the  proper  amount,  which  varies  greatly 
according  to  the  kind  of  insect.  A  few  drops  suffice  for  a  fly  while  some 
beetles  and  spiders  literally  must  be  bathed  in  it.  Care  must  be  taken  to 
remove  the  insect  after  it  is  properly  anesthetized.  Too  much  ether  will 
kill  it,  and  the  way  the  contracting  muscles  of  a  dying-  beetle  will  pull  its 
six  legs  into  a  tangle  would  discourage  the  most  patient  experimenter. 
Place  the  insect  quickly  on  the  gummed  tape  and  fasten  each  foot  in  the 
position  it  assumed  when  alive.  After  this  job  is  about  half  done  the 
chances  are  that  it  suddenly  will  come  to  life  and  pull  its  feet  free  so  that 
the  whole  operation  will  have  to  be  repeated. 

When  all  legs  are  in  place  the  insect  is  blocked  up  to  the  proper  height 
by  inserting  under  it  small  rolls  of  tinfoil  or  bits  of  cardboard.  The  head 
is  held  at  a  natural  angle  in  a  similar  way  or  by  letting  it  drop  into  the 
crotch  formed  by  two  pins  which  are  stuck  into  the  cardboard  in  such  a  way 
that  they  cross  just  under  the  head.  The  antenna  may  be  held  sloping 
upward  to  the  front  by  a  piece  of  cardboard  so  folded  that  one  part  of  it 
rests  flat  on  the  mount  forming  a  base  for  the  other  part  which  extends 
upward  at  the  desired  antenna  angle.  The  antennae  are  carefully  laid  on 
the  sloping  piece.  Antennae  which  are  carried  in  a  horizontal  position  may 
be  held  in  place  by  a  small  block  of  tinfoil  placed  under  them.  Legs  which 
tend  to  buckle  in  the  wrong  direction  are  braced  by  pins  stuck  into  the 


Fig.  216  The  praying 
Mantid  shown  in  Fig.  215 
after  the  Mounting  Pins, 
Blocks,  etc.,  have  been  Re- 

cardboard  mount.  Ordinary  pins  may  be  used  but  those  are  not  as  satis- 
factory as  the  pins  used  by  entomologists  for  mounting  insects.  This  pin 
is  about  1V2  inches  long  and  has  a  very  small  head  and  a  sharp  point. 
After  the  insect  is  finally  mounted  and  is  blocked  in  a  lifelike  position  it 
should  be  killed.  One  of  the  most  satisfactory  ways  of  doing  this  is  by 
inverting  a  large  mouthed  cyanide  bottle  over  the  insect.  The  cyanide 
fumes  do  their  work  in  a  very  few  minutes.  The  insect  is  carefully  put 
aside  to  dry  and  in  four  or  five  days  the  pins  and  blocking  may  be  removed. 
The  insect  will  remain  permanently  in  the  position  in  which  it  was  mounted. 
Figure  215  shows  a  praying  mantis  which  was  mounted  in  a  fighting  pose  by 
the  method  just  described.  Figure  216  shows  the  same  insect  as  finally 

The  supplies  and  implements  for  mounting  are  few  and  simple.  They 
are:  a  can  of  ether,  a  medicine  dropper,  some  pieces  of  cardboard,  a  small 
sheet  of  tin  or  lead  foil,  a  roll  of  gummed  cloth  mending  tape,  a  tube  of 
cement,  one  or  two  long  flexible  tweezers,  some  pins,  and  a  few  slender 
pieces  of  wood  with  needles  stuck  in  their  ends.  The  needles  are  used  for 
arranging  the  insect's  legs  and  antennae.  One  of  them  may  be  made  more 
useful  by  heating  the  needle  point  and  bending  it  into  a  very  short  hook. 
One  more  accessory  which  is  almost  a  necessity  is  a  binocular  loupe  magni- 
fier such  as  is  used  by  oculists.  Lacking  this  a  reading  glass  may  be  used 
but  it  should  be  mounted  on  a  support  so  that  both  hands  are  left  free  to 
work  on  the  insect. 

The  question  has  been  asked  many  times  as  to  how  insects 
should  be  preserved  to  prevent  decomposition.  The  answer  is  that 
preserving  is  not  necessary  for  the  reason  that  the  insect  wears  its 
skeleton  on  the  outside.  The  outer  part  of  the  insect's  body  is  com- 
posed of  a  substance  known  as  chitin.  This  is  an  organic  chemical 
compound  and  the  parts  of  an  insect's  skin  which  contain  it  are 
hard,  tough  and  lasting.  Spiders,  however,  require  special  treat- 
ment as  otherwise  the  body  will  gradually  shrink  and  collapse  until 
it  is  flat  and  unnatural  in  appearance.  Before  mounting  a  spider 
the  under  side  of  its  abdomen  should  be  slit  open  and  it  should  be 
thoroughly  cleaned  out.  It  should  then  be  stuffed  with  cotton  until 
it  is  filled  out  to  natural  size  and  appearance. 


Miniature  Monsters 

To  prepare  the  mounted  insect  for  photographing*  a  thin  layer 
of  fine  sand  may  be  sprinkled  on  the  cardboard  mount  to  produce  a 
natural  looking  foreground.  A  piece  of  cloth  or  cardboard  may  be 
placed  a  few  inches  beyond  the  insect  for  a  background.  This  may 
be  white,  black,  or  some  shade  of  gray  depending  upon  the  color  of 
the  insect  and  the  photographic  effect  desired.  For  a  dead  black 
background  a  piece  of  black  velvet  is  excellent. 


Lighting  a  subject  as  small  as  an  ant  or  a  fly  in  such  a  way  as 
to  bring  out  the  desired  contrasts  is  difficult  and  requires  much 
experimenting.  Almost  any  source  of  illumination  can  be  used,  but 
the  results  obtained  will  be  somewhat  dependent  upon  the  amount 
of  control  that  can  be  exercised  in  the  application  of  the  light.  The 
lighting  originally  used  by  the  writer  consisted  of  three  100-watt 
Mazdas  in  goose  neck  desk  lamps.  While  fairly  satisfactory  results 
were  obtained  with  this  lighting  arrangement  it  was  not  all  that 
could  be  desired.  The  size  of  the  light  source  was  so  large  com- 
pared to  the  subject  being  photographed  that  it  was  difficult  to 
produce  the  desired  effects.  Photoflood  lamps  may  be  used  if  it  is 
desired  to  materially  shorten  the  exposure  time,  but  these  too  have 
the  disadvantage  of  being  much  larger  than  the  subject. 

The  most  satisfactory  lamps  so  far  used  were  improvised  from  old 
style  De  Vry  still  projectors.  This  so  called  projector  really  consists  of  only 
a  lamp  housing  with  its  support  and  a  very  good  condenser  system.  Pro- 
jection originally  was  accomplished  by  clipping  a  De  Vry  camera  in  front 
of  the  condenser  and  using  the  camera  lens  as  the  projections  lens.  The 
camera  however  is  not  necessary  in  constructing  the  insect  spot  lights.  The 
first  steps  in  adapting  the  projector  are  to  remove  the  lamp  housing  from  its 
support,  discard  the  support  and  the  transformer  which  it  contains,  and 
substitute  a  double  contact  bayonet  socket  for  the  single  contact  socket. 
The  double  contact  socket  is  standard  and  may  be  obtained  in  any  automo- 
bile supply  store.  A  50  or  100  watt  115  volt  projection  bulb  will  fit  this 
socket  and  is  the  right  size  for  the  lamp  housing.  The  housing  should  then  be 
mounted  so  that  it  may  be  moved  up  and  down  or  may  be  tilted.  This 
requires  only  a  little  ingenuity  and  in  figure  217  it  is  shown  in  use.  It  con- 
sists of  a  lead-filled  lamp  base,  a  rod  with  sliding-  clamp  which  ordinarily  is 
used  to  adjust  casement  windows,  and  a  brass  coat  hanger  for  adjusting  the 
position  of  the  lamp  when  the  housing  becomes  too  hot  to  touch.  A  piece  of 
ground  glass  clamped  in  front  of  the  condenser  lens  to  diffuse  the  light  com- 
pletes the  outfit.  This  lamp  produces  a  brilliant  concentrated  spot  of  light  % 
inches  in  diameter  at  about  2%  inches  in  front  of  the  condenser  lens  and  a 
well  diffused  light  at  a  distance  of  eight  or  more  inches.  The  light  has  a 
value  of  1500  to  1800  candles  per  square  foot  in  the  %  inch  spot  and  about 
600  candles  at  the  8  inch  distance. 

In  arranging  the  lighting  in  preparation  for  the  exposure  a  good 
general  rule  is  to  place  lights  on  both  sides  of  the  subject  with  a 


Fig.  217  Close- 
up  View  of  Pho- 
tographic Equip- 
ment Showing1  Po- 
sition and  Con- 
struction of  Spot 
Light  and  Ar- 
rangement of  In- 
sect and  Lens 

third  light  above  and  to  the  front  of  the  insect.  In  order  to  avoid 
flat  lighting  the  lamps  should  not  be  equidistant  from  the  subject, 
but  should  be  so  placed  that  proper  shadows  are  cast.  Care  should 
be  taken,  however,  to  avoid  multiple  shadows.  By  changing  the 
position  of  one  or  more  lamps  any  desired  parts  of  the  insect  can  be 
thrown  into  relief.  A  useful  combination  of  lights  consists  of  two 
photoflood  lamps  with  tracing  cloth  diffusing  screens  and  a  single 
spot  light.  The  photofloods  are  placed  on  either  side  of  the  subject 
to  give  full  and  uniform  illumination  and  the  spot  is  used  to  bring 
out  the  desired  contrasts. 

Back  lighting  produces  interesting  results  and  seems  particu- 
larly effective  in  the  case  of  insects  having  semitransparent  wings. 
Entirely  different  effects  in  wing  photographs  may  be  produced  by 
back,  front  or  cross  lighting.  An  example  of  cross  lighting  is  shown 
in  figure  219.  This  is  a  photograph  of  the  almost  transparent  wing 

Fig.  218    Transparent  Wing  of  Small  Insect: 
Front  Illumination ;  White   Back-ground 

Fig.  219     Transparent  Insect  Wing,   Cross- 
Illuminated  Against  Dark  Back-Ground 


Miniature  Monsters 

of  a  small  insect.  The  beam  from  a  single  spot  light  was  directed 
across  the  surface  of  the  wing  in  order  to  make  the  wing  veins 
stand  out  in  relief.  In  contrast  to  this,  front  lighting  against  a 
white  background  silhouettes  the  veins  (fig.  218). 

Many  pitfalls  will  be  encountered.  The  smooth  shiny  body  of  a 
beetle  will  reflect  brilliant  patches  of  light.  Undesirable  reflections 
will  be  produced  by  the  eyes.  The  under  side  of  the  insect  will 
appear  on  the  print  as  a  black  area  with  no  detail  unless  care  is 
taken  to  place  one  or  more  lights  at  the  level  of  the  insects  body  or 
slightly  lower.  Many  other  difficulties  will  be  encountered  which 
can  be  solved  only  by  experiment.  In  general,  most  of  the  lighting 
principles  which  are  used  in  portrait  work  apply  equally  well  to 
the  photography  of  insects.  The  difficulty  lies  in  the  practical  appli- 
cation of  these  principles.  The  subject  is  so  small  and  the  effects 
of  the  lighting  are,  in  consequence,  so  difficult  to  judge  that  many 
times  it  is  only  when  the  final  enlargement  is  made  that  the  correct- 
ness of  the  lighting  arrangement  is  known. 

Ultraviolet  Light 

If  extreme  resolution  of  detail  is  required  it  will  be  necessary 
to  depart  from  the  usual  sources  of  artificial  light  and  to  take  advan- 
tage of  the  short  wave  lengths  of  the  ultraviolet  region.  An  inspec- 
tion of  the  equation  for  resolving  power  of  a  lens  will  show  that 
decreasing  the  wave  length  of  the  light  used  increases  the  resolving 

The  use  of  ultraviolet  light  for  photography  immediately  sug- 
gests quartz  lenses  and  quartz  lamps,  but  these  are  very  expensive 
and  are  not  necessary  for  ordinary  work.  The  usual  types  of  camera 
lenses  will  transmit  wave  lengths  from  the  visible  spectrum  down  to 
about  3300  Angstrom  units  which  is  sufficient  to  give  a  noticeable 
increase  in  definition. 

A  convenient  and  relatively  inexpensive  source  of  light  is  the 
Black  Bulb  ultraviolet  lamp  manufactured  by  the  "Westinghouse 
Lamp  Company  and  obtainable  through  any  of  their  local  offices. 
It  is  a  mercury  vapor  lamp  equipped  with  a  standard  screw  base. 
It  operates  at  15  volts  and  comes  in  two  sizes  having  2  amperes  and 
5  amperes  current  consumption  respectively.  The  lamp  transmits 
ultraviolet  wave  lengths  from  3200  to  4200  Angstrom  units,  which 
are  the  long  waves  of  the  ultraviolet  region  and  which,  incidentally, 
are  of  high  actinic  value  in  photography.  They  ai?e  not  harmful  to 
the  eyes. 


Great  care  should  be  taken  not  to  connect  these  lamps  to  the 
usual  110  volt  house  lighting  circuit  as  they  will  immediately  burn 
out.  They  should  always  be  used  In  series  with  a  suitable  reactance 
or  resistance  depending  upon  whether  they  are  to  be  connected  to  an 
alternating  or  a  direct  current  source. 

It  is  advisable  to  use  two  lamps  in  order  to  obtain  balanced 
lighting  of  the  subject,  and  the  exposure  time  will  be  reduced  if  they 
are  used  with  reflectors.  In  selecting  these  it  should  be  remembered 
that  a  reflector  which  is  quite  satisfactory  for  white  light  will  not 
necessarily  serve  for  ultraviolet.  Probably  the  best  compromise  be- 
tween reflection  efficiency  and  availability  of  the  material  is  aluminum 
oxide.  This  may  be  formed  on  the  surface  of  any  aluminum  re- 
flector by  immersing  it  in  a  strong  solution  of  lye.  It  should  be 
removed  and  washed  for  examination  at  intervals  of  two  or  three 
minutes  and  the  action  should  be  continued  until  the  aluminum  has 
a  uniform  matte  surface.  Just  two  words  of  caution — first  make 
sure  that  the  reflector  purchased  is  not  chromium  plated  on  the 
inside,  and  second,  do  not  breathe  the  fumes  .of  the  lye  bath. 

The  visible  light  from  the  Black  Bulb  is  so  faint  that  focusing  is 
impossible  and  must  be  done  by  white  light.  While  theoretically  the  ultra- 
violet will  cause  a  shift  of  focus,  practically  this  is  so  small  that  it  is  not 
noticeable  in  the  finished  picture.  The  exposure  time  will  be  much  longer 
than  with  the  usual  sources  of  artificial  light.  Definite  comparisons  are  dif- 
ficult because  of  the  lack  of  a  convenient  means  of  measuring  the  intensity 
of  the  ultraviolet  light  but  the  following  may  serve  as  a  rough  guide: 

Two  sets  of  exposures  of  the  same  subject  were  made,  using  in  one  case 
two  Black  Bulbs  in  aluminum  reflectors  and  in  the  other  case  one  small  spot 
light  equipped  with  a  100  watt  projection  bulb.  The  lights  in  each  case  were 
placed  at  about  the  same  distance  from  the  subject.  To  produce  negatives 
of  equal  density  required  about  150  times  as  long  an  exposure  with  the  ultra- 
violet as  with  the  white  light. 

The  improvement  in  definition  resulting  from  the  use  of  ultraviolet  light 
is  shown  in  figures  220  and  221,  These  are  photographs  of  the  eggs  which 

Fig.    220     Eggs   of  Canker  Worm  Fig.   221      Same   Section  of   Egg  Mass 

Photographed   by   Ultra- Violet    Light  Photographed    by    Mazda    Light 


Miniature  Monsters 

produce  the  inch  or  canker  worm  so  destructive  to  foliage.  Tlie  pictures 
were  taken  on  the  same  roll  of  film  with  the  same  lens  so  that  all  condi- 
tions except  the  light  source  were  identical. 

Increased  definition  is  only  one  of  the  results  of  the  use  of  ultraviolet. 
Experiments  conducted  by  Dr.  Frank  E.  Lutz  and  others  indicate  that  insects 
see  by  ultraviolet  rather  than  by  the  light  to  which  our  eyes  respond.  By 
using  the  short  invisible  waves  to  photograph  the  insects  we  are  able  to 
picture  them  as  they  possibly  look  to  each  other.  Comparison  photographs 
of  the  same  insect  taken  by  white  and  by  ultraviolet  light  will  in  some  cases 
reveal  interesting  differences  in  the  marking.  Figures  222  and  223  show 
two  photographs  of  a  butterfly  taken  in  one  case  by  white  light,  and  in 'the 
other  by  ultraviolet. 

Fig.   222     Yellow  Tiger   Swallow-Tail   But- 
terfly.    Photographed  by  Mazda  Light 

Fig.    223      Same    Butterfly.      Photographed 
by  Ultra- Violet   Light 

The  determination  of  the  best  film  to  use  in  ultraviolet  photography 
must  be  left  to  the  reader  to  determine,  as  the  writer  has  not  yet  had  time 
to  make  complete  comparative  experiments.  Dupont  Superior  Panchromatic 
with  which  the  accompanying  illustrations  were  made  has  given  excellent 
results,  although  possibly  other  films  may  be  found  which  are  better  suited 
to  this  light. 

Equipment  for  Indoor  Work 

In  preparing  the  photographic  apparatus  for  indoor  use,  the 
camera  should  be  so  mounted  that  the  axis  of  the  lens  is  horizontal, 
and  both  the  camera  and  the  platform  upon  which  the  insect  is  placed 
for  photographing  must  be  mounted  very  rigidly  in  order  to  elimi- 
nate vibration  and  consequent  loss  of  definition.  As  the  amount  of 
photographic  magnification  is  increased  this  becomes  a  serious  prob- 
lem and  unless  the  whole  structure  is  very  rigid  every  nearby  truck, 
train  or  street  car  will  cause  noticeable  vibration.  Another  matter 
of  importance  is  to  support  the  extension  tube  at  a  point  near  the 
lens.  If  this  is  not  done  the  vibration  will  be  excessive  no  matter 
how  firm  the  remainder  of  the  structure  may  be. 

One  of  the  arrangements  used  by  the  writer  is  shown  in  figure  224.  The 
bed  on  which  the  equipment  is  mounted  consists  of  two  5-ply  hard  wood 
panels  bolted  together  and  weighing  about  40  pounds.  Sponge  rubber 


Fig:.  224  James  M.  Leonard  and  his  Camera  Equipment  for  the  Photog- 
raphy of  Insects 

blocks  are  placed  between  the  panel  and  the  table  top  to  absorb  vibration. 
The  table  itself  rests  on  cork.  The  camera  is  attached  to  a  tripod  head  from 
an  old  German  machine  gun  mount.  These  can  be  picked  up  in  some  of  the 
stores  dealing  in  second  hand  war  material.  The  various  adjusting  screws 
on  the  tripod  head  make  it  possible  to  raise  or  lower  the  camera,  to  rotate 
it  from  side  to  side,  and  to  tilt  it  in  any  direction. 

The  mounting  bed  carries  a  heavy  walled  brass  tube  which  is  strongly- 
braced  and  on  which  are  two  Leica  sliding  arms.  The  outside  diameter  of 
the  tube  is  lx/4  inches  which  is  the  correct  size  to  fit  the  sliding  arms.  A 
small  platform  on  which  the  insect  is  placed  for  photographing  is  mounted 
on  one  arm  and  the  other  is  used  to  support  the  backgrounds.  The  platform 
can  be  moved  forward  or  back  by  means  of  a  rack  and  pinion.  A  movable 
support  for  the  end  of  the  extension  tube  rests  on  the  mounting  bed. 

Photographing  at  Home 

The  insect  to  be  photographed  is  placed  on  the  platform  and 
the  sliding  arm  is  moved  to  get  about  the  proper  working  distance 
between  the  lens  and  the  insect.  The  fine  focusing  adjustment  is 
made  by  means  of  the  rack  and  pinion. 

Having  put  the  insect  in  place  and  arranged  the  lights  all  that 
remains  to  be  done  is  to  focus,  expose,  develop  and  print.  These  few 
operations,  however,  bring  up  some  very  interesting  problems.  For 
example,  the  question  of  the  proper  diaphragm  opening  is  a  vexing 
one  and  usually  resolves  itself  into  a  compromise  between  depth  of 
focus  and  definition.  Stopping  down  the  diaphragm  increases  depth 


Miniature  Monsters 

Fig.  225     Amblicorypha  Oblongifolia — A  Relative  of  the  Katydid 

of  focus  but  in  the  case  of  some  lenses  results  in  a  loss  of  definition. 
Opening  it,  may  increase  the  resolving  power  but  gives  almost  no 
depth  of  focus.  A  fairly  wide  open  diaphragm  may  be  permissible 
when  photographing  an  insect  7s  head  or  other  part  which  will  not  in- 
clude the  foreground  or  the  mount  on  which  the  insect  is  placed.  If, 
however,  these  are  included  in  the  picture  the  result  will  be  far  from 
pleasing.  The  foreground  will  show  a  clean  cut  section  which  is  in 
sharp  focus  while  everything  in  front  of  and  beyond  this  section 
will  be  completely  out  of  focus.  As  the  diaphragm  is  closed  the  sec- 
tion in  focus  will  widen  and  the  line  of  demarcation  between  it  and 
the  out-of -focus  area  will  grow  less  distinct.  The  optimum  opening 
is  reached  when  the  areas  which  are  in  focus  and  those  which  are 
not  blend  into  each  other;  the  important  parts  of  the  insect  being, 
of  course,  in  focus. 

Some  difficulty  may  be  encountered  in  determining  whether  or 
not  the  insect  is  sharply  focused  because  of  the  small  amount  of  light 
reaching  the  ground  glass  when  the  diaphragm  is  partially  closed  or 
when  several  sections  of  extension  tube  are  used.  Focusing  will  be 
made  much  easier  if  the  ground  glass  is  given  a  light  coating  of  oil. 


Fig.   226    (left)      The  Poison  Sting  at  the   End 
of  a  Scorpion's  Tail 

Fig.     227       The    original     Zipper     Purse— The 
Egg  Case  of  a   Cockroach 

Coeoanut  oil  is  very  satisfactory  for  this  purpose.  Place  a  drop  on 
the  ground  side  of  the  glass  and  spread  it  with  the  finger,  rubbing 
lightly  in  one  direction  and  then  at  right  angles  to  that  direction  to 
insure  even  distribution  of  the  oil.  Do  not  use  cloth  to  spread  the  oil 
because  pieces  of  lint  are  likely  to  adhere  to  the  glass.  Wipe  the 
surplus  oil  from  the  finger  after  each  rubbing  in  order  to  reduce  the 
film  to  the  right  thickness.  The  proper  amount  remains  when  objects 
several  feet  distant  appear  indistinct  when  viewed  through  the  glass. 

The  proper  length  of  exposure  can  best  be  determined  by  the 
trial  and  error  method.  An  exposure  meter  will  help,  but  the  subject 
being  photographed  is  so  small  that  the  amount  of  light  which  it 
reflects  toward  the  lens  is  insignificant  compared  with  the  light  re- 
flected by  the  mount  or  the  background.  About  the  only  way  to  be 
sure  of  getting  a  usable  negative  is  to  make  four  or  five  exposures 
of  each  subject.  The  first  exposure  should  be  somewhat  shorter  than 
the  estimated  correct  time  and  each  succeeding  exposure  should  be 
V/2  or  2  times  the  preceding  one.  A  record  should  be  kept  of  the 
subject,  the  lighting  used,  the  length  of  the  extension  tube,  the  dia- 
phragm opening,  and  the  time  of  each  exposure.  A  study  of  such  a 
record  will  soon  enable  the  experimenter  to  make  a  sufficiently  good 
guess  at  the  exposure  time  so  that  if  not  more  than  three  exposures 
are  made  as  just  described  one  of  them  will  produce  a  negative  of  the 
correct  density. 

The  table  on  page  198  will  be  very  helpful  in  determining  the  relative 
exposure  for  any  length  of  extension  tube  and  includes  other  valuable  in- 


Miniature  Monsters 

formation  as  well.  Also  consult  the  chapter  on  Copying  and  Reproduction, 
by  Willard  D.  Morgan,  for  information  on  other  lenses  and  on  depths  of 

^  Any  reference  to  films  and  developers  may  seem  unnecessary.  These 
subjects  have  been  fully  covered  in  many  publications.  A  few  personal  opin- 
ions will  be  ventured,  however,  in  the  hope  that  they  may  help  the  beginner 
in  insect  photography.  If  extreme  definition  is  desired  the  order  of  pref- 
erence probably  should  be  (1)  positive  film,  (2)  orthochromatic  and  (3) 
panchromatic.  If  proper  rendition  of  the  colors  is  the  first  consideration 
the  order  should  be  reversed.  Many  insects,  particularly  the  moths  and  but- 
terflies are  marked  with  red  or  orange  and  if  the  various  gradations  and 
shades  of  these  colors  are  to  appear  in  the  finished  print  the  use  of  pan- 
chromatic film  is  essential. 

Fig.  228 

Fig.  229 

The  Life  Cycle  of  the  Spice-bush  Swallow-tail  Butterfly 

Fig.  230 


The  writer  has  adopted  DuPont  Superior  panchromatic  film  and  the 
so-called  Sease  No.  3  developer  for  his  own  use.  The  formula  for  this 
developer  has  been  published  many  times  but  will  be  repeated  here  for  the 
sake  of  completeness. 

Sodium  Sulfite   3  oz.  76  grains         90  grams 

Paraphenylene  Diamine  . . .  154  grains         10  grams 

Glycin   93  grains  6  grams 

Water    33  oz.  1  liter 

Developer  at  68°   F. 

Gamma  in  fourteen  minutes 0.62 

Gamma  in  tWenty-eigrht  minutes 1.09 

Gamma  in  forty-two  minutes 1.34 

Time  to  reach  0.7  gamma 17  minutes 

While  this  developer  has  the  disadvantage  of  requiring  approximately 
double  exposure  it  has  the  advantage  of  excellent  keeping  qualities  and  of 
producing  fine  grain.  The  writer  has  developed  twelve  rolls  of  film  in  a 
liter  over  a  period  of  months  and  the  developer  still  appeared  to  be  in  good 

It  is  hoped  and  believed  that  those  who  take  up  insect  photog- 
raphy will  find  it  a  fruitful  source  of  enjoyment  and  relaxation.  The 
use  of  a  little  imagination  in  departing  from  the  usual  procedure  of 
photographing  the  entire  insect  will  produce  interesting,  and  some- 
times amusing  results.  A  collection  of  insect  portraits  may  be  made, 
or  individual  parts  of  the  insect,  rarely  seen  in  detail  by  the  unaided 
eye,  may  be  photographically  enlarged.  Figure  225  is  a  typical  insect 
portrait,  the  subject,  in  this  case,  bearing  a  surprising  resemblance  to 
the  head  of  a  horse.  Figures  227  and  226,  the  egg  case  of  a  cockroach 
with  its  zipper  top,  and  the  poison-sting  which  is  the  scorpion's  weapon 
of  attack,  are  examples  of  parts  of  insects  so  enlarged  that  their 
details  may  be  seen.  Caterpillars  found  in  the  garden  or  the  field 
may  be  brought  home  to  develop  their  fascinating  and  mysterious  life 
cycle  within  reach  of  the  camera.  Figures  228  to  231  show  "four 
stages  in  the  life  cycle  of  Papilio-troilus,  the  Spice-bush  Swallow-tail 
butterfly.  These  few  suggestions  by  no  means  exhaust  the  possibilities 
of  this  interesting  branch  of  photography.  The  field  is  limited  only 
by  the  bounds  of  imagination. 

Fig.  232  Portion  of  Fig.  229.  Who 
is  the  Father  of  our  Country?... 





The  Leica  camera,  the  pioneer  of  miniature  cameras  has  opened 
so  many  new  fields  to  photography  and  has  been  used  successfully  for 
so  many  different  tasks  where  it  replaced  larger  cameras,  that  it  is  not 
surprising  when  it  enters  the  field  of  photomicrography. 

It  has  become  well  known  that  for  certain  types  of  photography 
the  miniature  camera  is  directly  essential,  due  to  special  optical  condi- 
tions which  are  verified  in  this  kind  of  camera.  The  combination  of 
high  speed  of  the  objective  and  depth  of  focus  in  the  picture  which 
has  been  thoroughly  discussed  in  the  chapter  on  lenses,  establishes  the 
necessity  of  miniature  cameras  for  many  special  tasks  such  as  candid 
photography,  photography  of  small  objects,  stage  photography  and 
others.  For  these  purposes  the  miniature  camera  is  essential  because 
it  does  what  no  larger  cameras  can  do.  When  trying  to  use  the  Leica 
camera  for  photomicrography  it  may  appear  upon  superficial  con- 
sideration that  something  paradoxical  is  being  attempted.  If  small 
objects  are  to  be  photographically  reproduced  at  a  high  ratio  of  magni- 
fication, it  seems  necessary  to  have  a  large  negative,  rather  than  crowd- 
ing the  enlarged  detail  again  into  a  small  negative.  The  sceptic  may 
readily  admit  that  photomicrography  with  a  miniature  camera  is  not 
altogether  impossible  but  he  may  consider  it  more  or  less  useless  or 
unsatisfactory  and,  at  any  rate,  not  specifically  advantageous.  It  is 
interesting  that  a  closer  investigation  of  the  optical  principles  proves 
beyond  doubt  that  for  certain  types  of  photomicrography  the  miniature 
camera  is  essential  and  it  is  only  with  its  help  that  some  apparently 
unsurmountable  difficulties  can  be  solved. 

When  to  Use  the  Leica  for  Photomicrography 

In  order  to  fully  appreciate  why  the  Leica  camera  can  be  used  for 
photomicrography  and  why  it  may  be  the  only  means  towards  achiev- 
ing success,  we  must  again  dive  into  several  intricate  optical  problems. 


Some  of  them  have  been  thoroughly  explained  in  the  chapter  on  Leica 
lenses  and  need  only  short  recalling. 

To  begin  with,  we  must  realize  that  the  very  purpose  of  pho- 
tomicrography is  to  record  minute  detail  which  is  so  small  that  it 
must  be  magnified  in  order  to  become  visible.  In  the  microscope  there 
are  two  lens  components  which  participate  in  the  process  of  magnify- 
ing, and  in  taking  the  photomicrograph  a  third  factor  enters  to  make 
the  process  complete  : 

1.  the  microscope  objective  forms  a  magnified  image  of  the  object 
under  investigation 

2.  the  eyepiece  of  the  microscope  remagnifies  this  image 

3.  the  distance  between  the  eyepiece  and  the  negative  on  which  the 
picture  is  recorded  determines  the  area  which  the  magnified  image 
finally  occupies  in  the  photograph. 

It  is  interesting  and  important  to  know,  that  only  the  first  of 
these  three  stages  of  magnifying  is  capable  of  revealing  finer  detail. 
The  function  of  the  eyepiece  and  the  projection  distance  in  recording 
the  image  on  the  negative  is  comparable  to  an  enlarging  process.  In 
the  enlargement  we  find  the  same  detail  which  was  in  the  negative  but 
stretched  over  a  larger  area  to  bring  it  within  the  limit  of  visibility  of 
the  eye.  Every  single  detail  which  we  find  in  the  enlargement  was 
also  in  the  negative,  only  it  may  have  been  so  close  together  that  the 
eye  could  not  see  it. 

In  photomicrography  we  find  all  revealable  detail  in  the  first 
magnified  image  which  the  objective  produces.  In  this  image,  how- 
ever, the  detail  is  crowded  into  such  small  space,  that  considerable 
enlargement  is  possible  before  it  is  fully  detectable  by  the  human  eye. 
We  could  place  the  negative  in  the  plane  where  the  objective  has 
formed  the  first  magnified  image  and  simply  enlarge  this  negative 
with  a  regular  enlarging  apparatus.  In  doing  this  we  would  meet  with 
some  technical  difficulties.  In  the  first  place  the  grain  size  of  the  silver 
deposit  in  the  finished  negative  would  limit  us  in  producing  greatly 
magnified  enlargements.  And  then,  as  was  mentioned  in  the  chapter 
on  lenses,  there  is  always  a  certain  loss  of  detail  in  recording  the  image 
on  the  turbid  emulsion  of  the  film.  The  light,  in  penetrating  through 
this  layer,  is  scattered  and  thus  the  rendition  of  detail  is  slightly 

Therefore  it  is  advisable  to  call  for  the  assistance  of  another  optical 
unit  to  participate  in  the  process  of  enlarging  the  image  which  the 
objective  has  formed.  But  although  we  can  let  the  eyepiece  carry  the 



entire  burden  of  the  enlarging  process  so  that  in  the  original  negative 
we  find  the  detail  separated  far  enough  to  make  it  visible  for  the  eye 
(in  which  case  a  contact  print  could  be  made  from  the  negative)  we 
may,  with  equal  justification,  divide  the  task  so  that  for  instance  in 
the  negative  the  detail  is  still  four  times  more  crowded  than  is  per- 
missible for  the  eye  to  see  it.  In  this  case  we  simply  enlarge  the  neg- 
ative again  four  times  in  our  regular  enlarger. 

The  realization  is  of  utmost  importance.  We  must  not  forget  that 
any  process  of  magnifying  is  naturally  connected  with  a  reduction  of 
the  light  intensity  in  a  given  area.  In  fact,  the  light  intensity  de- 
creases with  the  square  of  the  size  of  the  negative  so  that  for  instance 
in  taking  a  photomicrograph  on  a  plate  of  5  x  7  inches  we  require  an 
exposure  which  will  be  25  times  as  long  as  that  which  a  Leica  negative 
(1  x  11/2  in.)  requires  if  it  is  placed  so  much  closer  to  the  eyepiece,  that 

Fig.  233     Amoeba    Dubia 
lOx   Objective,   8x  Eyepiece 

Fig.    234      Chaetogaster 
3x  Objective,   8x  Eyepiece 

C.    G.    Grand 

the  same  area  of  the  object  is  reproduced  on  it.  There  are  many  occa- 
sions where  a  short  time  of  exposure  in  a  photomicrograph  is  essential 
because  the  specimen  under  the  microscope  may  be  living  and  moving 
around  so  that  it  can  only  be  photographed  by  instantaneous  exposure. 
Often  it  is  not  possible  to  increase  the  intensity  of  the  light  by  selec- 
tion of  a  stronger  light  source  because  the  enormous  concentration  of 
light  in  the  plane  of  the  object  may  quickly  destroy  the  delicate  struc- 
ture of  the  specimen.  In  these  cases  there  is  just  one  solution :  the 
miniature  camera.  It  is  not  surprising  that  it  was  the  important  field 
of  photomicrography  of  living  objects  which  came  to  its  full  practical 
significance  only  through  the  miniature  camera. 

But,  whereas  the  miniature  camera  is  indispensable  for  this  type 
of  photomicrography,  it  can  also  be  used  with  great  convenience  for 
many  tasks  of  general  photomicrography  without  serious  disadvan- 
tage. Whenever  a  great  many  photomicrographs  have  to  be  taken 
under  identical  light  conditions  and  magnification,  it  is,  of  course,  a 
great  convenience  to  have  the  Leica  with  its  gr^at  film  carrying  ca- 


pacity,  its  inexpensive  negative  material  and  the  great  variety  of 
film  emulsions.  General  Photomicrography  with  the  Leica  is  eco- 
nomical and  convenient.  Only  in  rare  cases  will  it  happen  that  the 
requirements  for  recording  even  the  very  minutest  detail,  are  such 
that  the  method  with  the  small  negative  may  show  slightly  inferior 
results  when  compared  to  photomicrographs  on  larger  negatives. 

Photomicrography  of  living  objects  and  general  photomicrography 
are  of  great  importance  for  the  scientist.  But  also  the  amateur  can 
become  interested  in  it  and  he  can  derive  an  infinite  amount  of  pleasure 
from  it.  So  we  have  a  rather  popular  field  of  application  for  the  Leica 
camera  in  photomicrography  as  a  hobby, 

To  summarize,  we  can  form  three  groups  and  this  classification  is 
not  arbitrary  but  has  quite  an  important  influence  upon  the  selection 
of  the  best  equipment : 

1.  Photomicrography  of  moving  objects :  the  Leica  is  a  necessity, 

2.  General  photomicrography :  the  Leica  is  an  economical  convenience, 

3.  Photomicrography  as  a  hobby:  the  Leica  is  a  source  of  pleasure. 

How  to  Adapt  the  Leica  Camera  to  the  Microscope 

In  describing  the  technique  of  photomicrography  with  the  Leica 
camera  we  must,  of  necessity,  give  preference  to  those  details  which 
relate  specifically  to  the  camera.  The  problems  pertaining  primarily  to 
microscopy  must  be  treated  more  briefly,  because  we  wish  to  condense 
the  information  into  a  chapter  rather  than  into  a  library.  Therefore 
we  shall,  for  the  present,  consider  the  microscope  as  one  unit,  and  the 
Leica  camera  as  another  one  and  then  describe  the  best  method  of  com- 
bining these  two  units  for  the  various  purposes  of  photomicrography. 

Among  the  accessories  offered  for  the  Leica  camera,  there  are 
devices  which  permit  three  different  ways  of  adaptation  of  the  camera 
to  the  microscope.  Which  of  these  three  devices  should  be  used, 
depends  again  upon  the  type  of  work  which  we  want  to  do. 

Fig.  235     Daphnia  Pulex 

C.  G.  Grand 

2x  Objective,  8x  Eyepiece 



Photomicrography  of  Living  Matter  with  the 
Micro  Ibso  Attachment 

When  using  the  Micro  Ibso  attachment,  the  regular  Leica  lens  must 
be  removed  from  the  camera.  That  means  that  this  attachment  can- 
not be  used  with  Leica  Model 
A.  The  attachment,  shown 
in  figure  236  is  to  be  adapted 
to  the  camera  body  like  a  reg- 
ular Leica  lens.  At  its  lower 
end  it  is  equipped  with  a 
microscope  eyepiece.  This  eye- 
piece has  a  magnifying  power 
of  10x  when  used  for  visual 
observation.  Used  in  connec- 
tion with  this  device,  however, 
this  power  is  not  fully  devel- 
oped because  the  small  nega- 

ms.  236  Micro-Ibso  Attachment  with  syn-  tiv6  °f  the  Lelca  Cam6ra  ls 
chronized  cable  releases :  one  activating  the  Com-  placed  SO  close  to  the  evepieee. 
pur  Shutter,  the  other  throwing  the  prism  out  ^  J  ^ 

of  the  path  of  light  rays  The  microscopist  knows  that 

only  if  the  negative  is  placed  10  inches  from  the  eyepiece,  the  mag- 
nification of  the  latter  in  photomicrography  will  be  equal  to  that 
which  prevails  in  visual  observation.  With  the  Ibso  attachment  the 
eyepiece  does  only  one-third  of  its  performance  for  visual  observa-. 
tion.  But  this  is  just  enough  to  spread  the  detail  conveniently  over 
the  area  of  the  Leica  negative.  That  means  that  a  Leiea  negative, 
enlarged  to  the  size  of  3  x  4%  inches  will  represent  a  photomicrograph 
with  the  same  magnification  as  that  which  prevailed  if  the  same  ob- 
jective and  eyepiece  would  have  been  used  for  visual  observation. 

The  eyepiece  can  be  removed  from  the  Ibso  attachment  by  un- 
screwing the  knurled  adapter  ring  with  which  the  entire  device  is 
clamped  to  the  microscope  tube.  It  is  not  advisable  to  use  eyepieces 

of  different  magnifiying  power.  It 
must  be  realized  that  the  field  seen 
through  the  microscope  is  circular 
whereas  the  shape  of  the  negative  is 
rectangular.  On  the  other  hand  we 
find  in  photomicrography  that  it  is 

Fig.  237  Leica  Photomicrograph 
made  with  the  Micro-Ibso  Attach- 


often  next  to  impossible  to  have  the  entire  field  appear  uniformly 
sharp  in  focus.  Especially  at  higher  magnification  the  outer  portion 
of  the  field  is  more  or  less  out  of  focus.  The  eyepiece  with  which  the 
Ibso  attachment  is  equipped  has  such  magnifying  power  that  the  most 
valuable  portion  of  the  field  is  utilized.  How  the  image  of  the  speci- 
men fills  the  frame  of  the  Leica  negative  is  shown  in  figure  237. 

Fig.  238     Micro-Ibso  Attachment  with  Leica  camera 
placed  upon  Microscope — -ready  to  use 

The  middle  section  of  the  Ibso  attachment  contains  a  beam- 
splitting  prism  which  can  be  removed  from  the  course  of  rays  by 
operation  of  a  wire  release.  So  that  this  prism  may  also  be  held 
outside  of  the  course  of  rays,  the  wire  release  is  equipped  with  a  clamp- 
ing screw.  A  certain  portion  of  the  light  which  has  passed  through 



the  microscope  is  reflected  by  the  prism  into  a  side  telescope  where  the 
micro  image  can  be  visually  observed  and  focused.  The  balance  of  the 
light  passes  onto  the  film.  Above  the  telescope  there  is  a  Compur 
shutter  with  which  the  actual  exposure  is  made.  A  conical  housing 
is  attached  to  the  middle  section  and  this  is  of  such  length  that  the 
image  will  fill  the  negative  as  shown  before.  This  housing  also  con- 
tains a  lens  system  for  the  purpose  of  correcting  the  passage  of  the 
rays  so  that  at  this  short  distance  a  sharp  image  can  be  produced. 

It  is  the  beam-splitting  prism  and  the  side  telescope  which  make 
the  Ibso  attachment  so  valuable  for  photomicrography  of  living 
objects.  When  the  specimen  is  in  motion  it  is  essential  that  we 
have  a  method  of  observing  and  focusing  continuously  until  the  very 
instant  before  the  exposure  is  taken  and  these  two  features  enable  us 
to  do  so. 

And  in  order  to  shorten  the  time  of  exposure  as  much  as  possible 
we  do  not  only  benefit  from  the  small  negative  size  of  the  Leica  but 
also  from  the  fact  that  during  the  (general  instantaneous)  exposure 
the  beam-splitting  prism  is  removed  from  the  course  of  rays,  thus  con- 
veying the  entire  available  amount  of  light  onto  the  film. 

The  side  telescope  is  equipped  with  an  adjustable  eyelens.  This 
is  an  important  device  which  is  often  overlooked.  When  focusing 
visually  we  must  realize  that  there  are  differences  in  the  eyesight  of 
different  observers.  When  the  image  appears  in  focus  for  one  ob- 
server, it  may  not  be  sharp  for  another;  yet  the  image  must  always 
be  sharp  in  the  plane  of  the  film.  These  differences  are  compensated 
by  the  adjustable  eyelens.  In  looking  through  the  side  telescope  a 
cross  hair  ruling  is  visible.  Before  focusing  the  microscope  the  ob- 
server must  turn  the  mount  of  the  adjustable  eyelens  until  the  cross 
hairs  appear  in  perfect  focus.  Only  when  this  is  done  should  the 
microscope  be  focused  with  the  coarse  and  fine  adjustment.  In  this 
case  there  will  aways  be  coincidence  of  focus  in  the  side  telescope 
and  in  the  plane  of  the  film.  If  a  different  observer  looks  through 
the  side  telescope  and  finds  the  micro  image  out  of  focus,  the  cross 
hairs  will  likewise  lack  in  sharpness.  But  simply  by  turning  the 
mount  of  the  adjustable  eyelens  crisp  focus  can  be  established  for 
both,  the  image  and  the  cross  hairs. 

It  may  appear  strange  that  a  Compur  shutter  is  required  to 
take  the  photo  inasmuch  as  the  Leica  camera  has  a  focal  plane  shutter. 
This  shutter,  however,  when  released,  moves  in  a  direction  which 
would  create  a  lateral  momentum  and  cause  vibrations  which  would 
affect  the  sharpness  of  the  picture.  The  Compur  shutter  avoids  this 


danger.  But  since  the  transporting  of  the  film  is  coupled  with  the 
winding  of  the  Leiea  shutter,  the  procedure  of  taking  successive 
photomicrographs  is  somewhat  complicated  and  the  photomierographer 
will  have  to  accustom  himself  to  the  following  sequence  of  manipula- 

1.  Remove  the  lens  from  your  Leica  camera  and  adapt  in  its  place  the 
Micro  Ibso  attachment  to  the  camera  body  of  Leica  models  C,  D,  E, 
F,  FF,  or  G. 

2.  Remove  the  regular  eyepiece  from  the  microscope  tube,  set  the  tube 
to  the  correct  mechanical  tubelength  prescribed  by  the  manufacturer 
(some  microscopes  are   equipped  with   draw-tubes,  others  have   sta- 
tionary tubes;  the  manufacturers  have  different  standards  as  to  the 
length  of  the  tube  and  when  the  microscope  is  equipped  with  a  draw 
tube,  this  must  be  correctly  set)   and  place  a  rubber  ring  or  metal 
clamp  around  the  draw-tube  so  that  the  weight  of  the  camera  with 
Ibso  attachment  will  not  change  the  tubelength.     A  rubber  ring  is 
supplied  with  the  Ibso  attachment. 

3.  Adapt  the  Ibso  attachment  with  Leica  camera  to  the  microscope  by 
inserting  the  eyepiece  of  this  attachment  into  the  microscope  tube. 
Then  tighten  the  clamping1  screw  on  the  knurled  ring  at  the  lower  end 
of  the  Ibso  attachment. 

4.  Fasten  the  two  wire  releases  to  the  Ibso  attachment.     The  one  with 
clamping  screw  is  for  the  beam-splitting  prism,  the  other  one  is  for  the 
Compur  shutter. 

5.  Attach  the  regular  wire  release  to  the  Leica  camera.    Wind  the  focal 
plane  shutter  of  the  Leica  camera  and  set  it  for  time  exposure. 

6.  Adjust  the  eyelens  of  the  side  telescope  so  that  the  cross  hairs  appear 
in  sharp  focus. 

7.  Focus  the  image  of  the  microscope  with  coarse  and  fine  adjustment 
while  looking  through  the  side  telescope. 

8.  Set  the  Compur  shutter  for  the  correct  time  of  exposure. 

9.  Press  the  wire  release  of  the  Leica  camera  and  clamp  the  wire  release 
in  this  position  so  that  the  focal  plane  shutter  will  remain  open.    You 
are  now  ready  to  take  the  exposure  by  pressing  the  wire  release  of  the 
Compur  shutter.     If  you  wish  to  have  as  much  light  as  possible  for 
the  exposure,  you  can  also  swing  the  beam-splitting  prism  out  of  the 
course  of  rays.    Thus  you  will  have  to  operate  two  wire  releases  simul- 
taneously.    But  you  must  also   operate  the   fine   adjustment  of  the 
microscope  continuously  and  since  we  have  only  two  hands,  you  may 
wish  to  make  use  of  an  automatic  release  attachment  which  permits 
with  one  motion  to  swing  out  the  prism  and  immediately  afterwards 
to  take  the  exposure.    This  attachment  is  likewise  shown  in  fig.  238. 

10.  After  the  exposure  has  been  taken,  loosen  the  clamping  screw  of  the 
Leica  wire  release,  thus  closing  the  focal  plane  shutter.  Wind  to  the 
next  frame,  press  the  Leica  release  again,  clamp  it  in  this  position 
and  you  are  ready  for  the  next  picture. 

Whereas  the  Ibso  attachment  can,  of  course,  be  used  for  every 
task  in  photomicrography  with  the  Leica  camera,  regardless  of  whether 
the  object  is  moving  or  stationary,  other  devices  may  be  preferred  in 



the  latter  case.  The  Ibso  attachment,  after  all,  is  not  inexpensive  and 
other  Leiea  accessories  may  be  used  equally  well,  having  the  added 
advantage  of  the  possibility  of  other  applications. 

General  Photomicrography  with  the  Sliding  Focusing  Attachment 

Excellent  photomicrographs  can  be  taken  with  the  Leica  camera 
adapted  to  the  sliding  focusing  copy  attachment  when  the  latter  is 
attached  to  the  extension  arm  on  the  upright  of  the  Valoy  enlarger 
(or  other  models)  and  is  provided  with  an  extension  tube  of  a  certain 
minimum  length.  Also  in  this  case,  Leiea  Model  A  cannot  be  used 
because  the  camera  body  alone  must  be  attached  to  the  focusing  at- 
tachment. The  general  set-up  is  shown  in  figure  239.  After  having 
removed  the  lamp  housing  from  the  upright  of  the  enlarger,  the  spe- 

Fig.  239  General  set-up  showing  how  a  Sliding  Focusing  Attachment  is 
used  with  the  Leica  for  Photomicrographic  work. 

cial  arm  which  holds  the  focusing  attachment  with  the  Leica  camera 
is  fastened  to  the  upright.  An  extension-tube  of  6cm,  should  be  used 
attached  to  the  sliding  focusing  attachment.  The  arm  carrying  the 
entire  Leica  equipment  is  lowered  until  microscope  tube  and  extension 


tube  just  overlap.  A  light-proof  connection  can  easily  be  established 
by  wrapping  a  piece  of  black  paper  or  cloth  around  the  lower  end  of 
the  extension  tube.  * 

It  is,  of  course,  possible  to  use  extension  tubes  of  any  length.  The 
total  length  of  the  tubes  used  will  determine  the  magnification  of  the 
image  in  the  plane  of  the  film  and  therefore  also  the  area  which  the 
image  occupies.  A  tube  of  6cm.  has  been  suggested  for  definite  rea- 
sons. When  this  tube  is  used,  the  image  will  occupy  about  the  same 
area  as  that  shown  in  fig.  237,  when  an  eyepiece  of  10s  magnifica- 
tion is  used,  as  in  the  ease  of  the  Ibso  attachment.  It  is  also  possible 
to  use  eyepieces  of  different  magnifying  power.  When  these  eyepieces 
are  used  for  such  short  projection  distances  they  do  not  yield  their 
total  magnifying  power  which  would  prevail  in  visual  observation. 
Only  if  the  total  distance  from  the  rim  of  the  eyepiece  to  the  plane  of 
the  film  is  10  inches  will  the  eyepiece  yield  the  same  magnifying 
power  as  in  visual  observation.  For  shorter  distances  this  power 
decreases  correspondingly.  When  the  total  distance  is  only  about 
3  1/3  inches  (as  it  will  be  when  the  6cm  tube  is  used)  the  eyepiece 
magnification  is  also  reduced  to  1/3  of  its  full  value,  which  corresponds 
to  that  which  we  use  when  taking  photomicrographs  with  the  Ibso 

For  those  who  want  to  proceed  in  strictest  accordance  with  cor- 
rect optical  principles  it  may  be  mentioned  that  when  taking  photo- 
micrographs with  the  focusing  attachment,  they  may  use  eyepieces 
with  adjustable  eyelenses  to  compensate  for  the  short  projection  dis- 
tance. The  principle  involved  is  too  complicated  and  the  benefit  de- 
rived too  minute  to  require  special  explanation.  The  reader  who  is 
interested  is  referred  to  literature  about  microscopy. 

The  procedure  in  taking  photomicrographs  with  this  equipment 
is  as  follows : 

1.  Before  placing  the  focusing  attachment  with  Leica  camera  and  exten- 
sion tube  in  position,  focus  the  microscope  roughly  for  visual  observa- 
tion so  that  the  microscope  tube  will  not  have  to  be  displaced  too  much 
in  vertical  direction  after  the  light-proof  connection  has  been  estab- 

2.  When  the  microscope  has  been  focused  visually,  lower  the  arm  on  the 
upright  until  the  extension  tube  overlaps  the  microscope  tube  and  make 
the  light-proof  connection.     Tighten  the  clamping  screw  on  the  exten- 
sion arm  when  the  image  on  the  ground  glass  appears  as  shown  in 
figure  2  (provided  a  lOx  eyepiece  and  6cm  tube  were  used). 

3.  Attach  the  wire  release  to  the  Leica  camera. 

4.  Focus  the  image  sharply  on  the  ground  glass  by  means   of  the  fine 
adjustment  of  the  microscope  and  slide  the  Leica  camera  into  position. 
You  are  now  ready  to  take  the  photomicrograph. 



When  the  focal  plane  shutter  is  released  there  Is  no  danger  of  vibra- 
tions affecting  the  sharpness  because  the  Leica  camera  is  held  rigidly  in 
the  focusing  attachment. 

Obtaining  Critical  Focus 

Critical  mieroscopists  may  resort  to  a  simple  trick  in  order  to 
avoid  any  error  in  focusing  on  the  ground  glass.  A  small  piece  of 
thin  clear  glass,  such  as  a  cover  glass,  used  for  protection  of  micro 
slides,  may  be  pasted  to  the  ground  glass  with  a  small  droplet  of  cedar 
wood  oil.  The  covered  area  will  become  transparent  and  the  aerial 
image  may  be  focused  with  a  special  30x  magnifier  (a  special  ground 
glass  with  a  clear  strip  and  calibrated  scale  is  also  available).  This 
magnifier,  however,  must  also  be  focused  to  the  plane  of  the  cover- 
glass.  Therefore,  before  attaching  the  coverslip,  a  small  pencil  mark 
should  be  made  on  the  ground  glass.  The  magnifier  may  be  raised  or 
lowered  in  its  mount  until  this  pencil  mark  appears  in  sharp  focus. 
Then  the  fine  adjustment  of  the  microscope  must  be  operated  until 
the  micro  image  also  appears  in  sharp  focus. 

The  results  which  can  be  obtained  with  this  equipment  are  so 
satisfactory  that  for  many  purposes  of  general  photomicrography  it 
finds  more  and  more  extensive  use.  As  long  as  stationary  objects  are 
to  be  photographed  it  is  often  preferred  to  the  Ibso  attachment  be- 
cause it  seems  easier  to  obtain  a  critical  focus  although  with  some 
training  the  other  method  yields  equivalent  results. 

There  is  another  method  of  photomicrography  with  the  Leica 
camera  which  requires  less  equipment.     This  method  may  be  sug- 
gested to  the  amateur  who  may  not  wish  to  go  too  deeply  into  this  type 
of  work. 
Amateur  Photomicrography  with  the  Micro  Adapter  Ring 

"When  using  the  Leica  camera  with  the  micro  adapter  ring  the 
lens  must  be  left  in  the  camera.  Therefore  it  is  also  possible  to  use 
Leica  Model  A  for  this  type  of  photomicrography.  The  micro  adapter 
ring  is  slipped  over  the  tube  of  the  microscope  and  its  upper  part  is  so 
shaped  that  it  can  be  adapted  to  the  rim  of  the  Leica  lenses  of  50mm 
focal  length  like  a  light  filter. 

The  method  of  focusing  is  as  simple  as  it  is  interesting.  Focus 
the  microscope  for  visual  observation,  focus  the  Leica  camera  inde- 
pendently for  infinity  and  then  place  it  over  the  microscope  into  the 
micro  adapter  ring  where  it  is  held  in  place  by  tightening  the  clamp- 
ing screw  in  the  upper  part  of  the  adapter. 

This  method  of  focusing  is  so  interesting  because  it  reminds  us  of 
the  fact  that  the  human  eye  is  really  a  very  small  miniature  camera, 
perhaps  the  most  remarkable  miniature  camera  in  existence.  The 


human  eye  is  equipped  with  a  lens  which  forms  images  on  the  retina. 
But  this  lens  has  no  focusing  mount  and  yet  it  can  be  focused.  It  is 
certainly  a  most  wonderful  creation.  Since  nature  preferred  not  to 
provide  our  eyes  with  bellows  or  focusing  mounts  which  would  permit 
to  change  the  distance  between  the  lens  and  the  retina,  the  lens  in 
the  human  eye  focuses  itself  automatically  by  changing  its  focal 
length  according  to  the  distance  from  which  we  look  at  the  object. 
When  this  distance  is  small,  the  lens  increases  its  curvature  (eon- 
trolled  by  a  most  ingenious  mechanism  of  muscles)  to  shorten  fts 
focal  length  until  the  image  is  sharp  on  the  retina.  If  the  object  is 
farther  away  the  muscles  relax  and  decrease  the  curvature  to  increase 
the  focal  length  just  enough  to  have  again  a  sharp  image  on  the 
retina.  And  this  complicated  mechanism  works  so  perfectly  that  we 
operate  it  unconsciously  and  instantaneously  as  soon  as  we  open  our 

Nevertheless  it  is  a  strain  for  the  eye  when  it  looks  at  an  object 
at  close  distance  whereas  it  relaxes  as  much  as  possible  when  it 
looks  at  an  object  which  is  infinitely  far  away.  And  since  the 
microscopist  must  often  look  through  the  instrument  for  long  pe- 
riods at  a  time  the  scientists  designed  the  optical  equipment  of 
microscopes  so  that  the  eye  can  be  as  much  at  ease  as  possible.  In 
other  words  the  lens  in  the  eye  focuses  itself  as  if  it  would  have  to 
look  at  an  object  at  infinity.  And  if  we  replace  the  human  eye  by 
another  miniature  camera  (or,  for  that  matter,  by  any  photographic 
camera,  regardless  of  size)  the  lens  of  this  camera  must  likewise  be 
focused  to  infinity. 

Not  every  observer  has  perfect  eyesight.  Some  are  near  sighted 
others  are  far  sighted.  That  means  that  their  focusing  mechanism 
is  out  of  order.  Such  defects  may  happen  to  the  focusing  mechanism 
of  other  miniature  cameras.  But  as  long  as  we  deal  with  manufactured 
cameras  we  can  send  them  to  the  manufacturer  for  readjustment.  He 
can  determine  the  amount  of  the  error  and  can  either  place  an  inter- 
mediate ring  under  the  objective  mount  or  he  can  shorten  this  mount 
until  the  images  are  always  in  focus  if  we  operate  the  focusing 
mechanism  with  the  rangefinder.  Unfortunately  there  are  no  similar 
repair  shops  for  our  eyes  so  that  we  must  content  ourselves  with  a 
correction  of  the  discrepancy  by  adding  front  lenses  which  we  call 
spectacles,  to  the  lens  of  the  eye.  And  everybody  who  must  wear 
eyeglasses  for  correction  of  defects  of  his  eyelenses,  should  always 
leave  them  on  when  focusing  the  microscope  visually  before  taking 
pictures  with  the  Leica  and  Micro  Adapter  Ring, 



Before  adding  the  weight  of  the  Leica  camera  with  adapter  ring 
to  the  microscope  it  is  also  advisable  to  attach  a  rubber  ring  or  a 
metal  clamp  to  the  draw  tube  of  the  microscope  at  the  correct  length. 

The  distance  between  the  Leica  camera  and  the  microscope  is 
now  so  small  that  the  magnifying  power  of  the  eyepiece  is  still 
further  reduced  to  only  one-fifth  of  its  power  for  visual  observation. 
In  other  words,  if  the  Leica  negative  is  enlarged  five  diameters  the 
final  print  will  represent  a  photomicrograph  which  has  the  same  mag- 
nification which  would  have  prevailed  in  visual  observation  with  the 
same  objective  and  eyepiece.  Figure  241  shows  the  relation  between 
the  Leica  negative  and  the  area  covered  when  taking  a  photomicro- 
graph with  the  micro  adapter  ring,  using  an  eyepiece  of  12x  magnifica- 
tion. Eyepieces  of  different  magnifying  power  can  also  be  used,  but 
sometimes  it  will  be  difficult  to  avoid  internal  reflections  within  the 
optical  system. 

Fig.  240  Placer  Gold.  Photomicrograph 
by  R.  E.  Head,  made  with  Ultropak  and 

Fig.  241  11/eica  used  with  Micro 
Adapter  Ring  and  12x  Eyepiece 
covers  area  shown 

The    procedure    of   taking    photomicrographs    with    the    Micro 
Adapter  Ring  can  be  summarized  as  follows : 

1.  Set  the  draw  tube  of  the  microscope  to  the  correct  length  and  fasten  a 
rubber  ring1  or  metal  clamp  so  that  this  tube  length  will  be  maintained 
when  the  Leica  camera  is  placed  into  the  Micro  Adapter  Ring. 

2.  Detach  the  black  lacquered  upper  part  of  the  Micro  Adapter  Ring  from 
the  lower  metal  part,  withdraw  the  eyepiece  from  the  microscope  tube, 
fasten  the  lower  part  of  the  ring  to  the  tube  and  tighten  the  clamping 

3.  Insert  the  eyepiece  into  the  microscope  tube  and  attach  the  upper  part 
of  the  Micro  Adapter  Ring. 

4.  Focus  the  microscope  for  visual  observation. 

5.  Focus  the  Leica  camera  independently  for  infinity.     Attach  the  wire 
release  and  wind  the  shutter  which  must  subsequently  be  set  for  the 
correct  time  of  exposure. 

6.  Attach  the  Leica  camera  carefully  to  the  upper  part  of  the  Micro  Adapter 
Ring  and  tighten  the  upper  clamping  screw.    You  are  now  ready  to  take 
the  photomicrograph. 


Those  who  possess  an  enlarger  and  an  extension  arm  may  prefer  to 
attach  the  Leica  camera  to  this  arm,  place  the  microscope  with  the  adapter 
ring  on  the  baseplate  of  the  enlarger  and  lower  the  arm  until  the  Leica 
lens  mount  connects  with  the  upper  part  of  the  Micro  Adapter  Ring.  Thus 
the  weight  of  the  Leica  camera  does  not  rest  on  the  microscope.  This  has 
not  only  the  advantage  of  avoiding  the  danger  of  vibrations  when  releasing 
the  shutter  but  also  that  of  affecting  the  accurate  focus,  especially  at  high 

This  method  of  photomicrography  with  the  Leica  camera,  incidentally 
is  optically  the  most  correct  one  because  the  microscope  retains  the  same 
focus  as  for  visual  observation  and  the  correction  of  the  entire  optical 
system  of  the  microscope  is  at  its  best  under  these  conditions. 

How  to  Select  the  Microscope 

For  Photomicrography  of  Living  Matter 

Whereas  prepared  microscopic  specimens  are  generally  mounted 
on  glass  slides  as  thin  sections  and  can  be  observed  by  sending  light 
through,  them,  living  organisms  or  unprepared  objects  are  mostly 
more  or  less  opaque  and  of  irregular  shape.  They  not  only  require 
a  microscope  stand  of  special  design  but  also  special  illumination 
arrangements.  These  illumination  devices  also  influence  the  design 
of  the  microscope. 

As  long  as  these  opaque  objects  are  to  be  photographed  at  low 
magnification  the  illumination  offers  no  difficulties.  Under  these  con- 
ditions the  distance  between  the  front  lens  of  the  microscope  objective 
and  the  object  is  comparatively  long.  (This  distance  is  generally 
called  working  distance,  a  term  which  should  not  be  confused  with  the 
focal  length  of  the  objective) .  The  light  emitted  by  a  suitable  micro- 
scope lamp  may  be  concentrated  by  a  so-called  bull's  eye  condenser 
and  may  be  so  guided  that  it  falls  obliquely  upon  the  surface  of  the 
specimen.  But  as  the  magnification  increases  the  working  distance 
decreases  so  rapidly  that  even  at  moderately  high  magnification  there 
is  not  enough  clearance  between  objective  and  specimen  to  squeeze 
the  light  between  the  two. 

Microscopists  who  examine  the  surface  structures  of  metals  use 
a  device  known  as  vertical  illuminator.  It  is  attached  to  the  lower 
end  of  the  tube.  The  light,  entering  laterally,  is  reflected  into  the 
direction  of  the  optical  axis  of  the  microscope  and  passes  through  the 
objective  which  simultaneously  acts  as  a  condenser,  to  concentrate  the 
light  in  the  plane  of  the  object.  From  the  surface  of  the  object  the 
light  is  reflected  and  passes  again  through  the  objective  which  now 
acts  as  an  image  forming  unit. 

This  method  of  illumination,  which  yields  satisfactory  images  of 
the  highly  reflecting  polished  and  plane  surfaces  of  metals,  fails  if 



applied  to  the  illumination  of  rough  low  reflecting  and  uneven  sur- 
faces of  organisms  or  other  materials.  As  the  light  passes  through 
the  objective  on  its  way  to  the  specimen,  partial  reflections  occur 
at  the  surfaces  of  the  different  lenses  which  produce  a  haze  thus 
greatly  reducing  the  contrast  in  the  image.  This  haze  may  even 
obliterate  the  detail  completely. 

The  situation  can  be  compared  with  one  which  you  undoubtedly 
have  often  observed:  a  picture  hanging  on  the  wall  may  be  covered 
with  a  glass  plate.  Under  certain  light  conditions  the  glare  produced 
through  reflections  of  light  by  the  glass  plate  may  be  so  strong  that 
you  cannot  see  the  picture  at  all. 

Another  illumination  method  was  developed  for  observation  of 
objects  of  low  reflecting  power  which  avoids  the  double  passage  of 
light  through  the  objective  and  can  be  used  even  at  the  highest  mag- 
nifications. The  device  used  for  this  purpose,  the  Leitz  UUropak, 
was  introduced  only  a  few  years  ago  and  it  has  pioneered  this  im- 
portant and  utterly  fascinating  field  of  microscopic  observation  and 
photomicrography  of  opaque  objects  with  surfaces  of  low  reflecting 
power  at  high  magnification.  The  illuminator  is  shown  in  figure  242. 
The  light,  entering  horizontally,  is  reflected  by  a  ring-shaped  mirror 
and  passes  through  a  condenser  system  which  surrounds  the  objective. 
This  condenser  collects  the  light  so  that  it  illuminates  the  object  with 
highly  oblique  rays.  From  the  rough  surfaces  of  the  object  the  light 
is  diffusely  reflected,  passes  through  the  objective,  a  central  hole  in 
the  ring-shaped  mirror  and  forms  the  image. 

I  —  Sector  diaphragm 
I  Slit  for  filters 

with  Fi£*    242      Bias*8-1*1    showing 

screwed  on 


The  Ultropak  is  attachable  to  every  standard  microscope  tube. 
It  is  equipped  with  a  small  incandescent  lamp  which  is  satisfactory 
for  visual  observation  but  not  strong  enough  for  instantaneous  photo- 
micrography. In  such  cases  a  more  powerful  light  source  such  as  an 
arc  lamp  must  be  used.  A  special  lens  system  can  be  attached  to  the 
light  entrance  tube  of  the  Ultropak  to  concentrate  this  light.  The 
complete  equipment  assembled  for  photomicrography  with  the  Ibso 
attachment  is  shown  in  figure  243. 

Fig.  243    Micro-Ibso  Attachment  with  Microscope  and  Arc  Lamp  for  Pho- 
tomicrography of  living  matter 

This  arrangement  makes  a  special  type  of  microscope  almost  im- 
perative. Generally  a  microscope  is  focused  by  raising  or  lowering 
the  tube  which,  for  this  purpose,  is  equipped  with  a  coarse  adjust- 
ment by  rack  and  pinion  and  a  fine  adjustment  by  micrometer  screw. 
The  arc  lamp,  however,  not  being  attached  to  the  tube,  would  not 
follow  these  focusing  motions  and  the  horizontal  beam  would  not 
always  pass  through  the  condenser  lens  which  is  attached  to  the 
Ultropak.  In  other  words,  the  operation  of  focusing  the  microscope 
would  throw  the  illumination  system  out  of  alignment.  This  diffi- 
culty can  be  overcome  by  using  a  type  of  microscope  where  the 
coarse  focusing  is  done  by  raising  or  lowering  the  object  stage. 

Microscopes  of  this  type  provide  for  much  space  between  the  tube 
and  the  stage  so  that  even  comparatively  large  objects  may  be  placed 
on  the  stage  in  their  entirety.  These  models  are  recommended  for 



photomicrography  of  objects  which  make  the  method  of  illumination 
by  Ultropak  or  vertical  illuminator  necessary.  They  are  of  such 
design  that  substage  illuminators  for  photomicrography  by  transmit- 
ted light  can  be  attached  to  them. 

For  General  Photomicrography 

As  mentioned  before,  specimens  which  have  been  specially  pre- 
pared for  microscopic  observation  are  generally  mounted  as  thin  sec- 
tions on  glass  slides  and  they  are  illuminated  by  sending  the  light 
through  the  thin  layer  of  the  object.  The  structures  may  allow  only 
certain  colors  of  the  light  to  pass  through,  whereas  others  are  absorbed. 
These  structures  will  become  visible  in  those  colors  which  could  pass 
through  them.  It  may  be  that  other  structures  absorb  all  colors 
equally,  either  completely  or  partly,  and  those  structures  will  appear 
black  or  any  shade  of  gray  against  the  lighter  background.  In  other 
words,  the  structures  become  visible  because  of  partial  transmission 
of  light  and  the  illumination  method  for  these  objects  is  generally 
called  "by  transmitted  light.  The  variety  of  microscopes  available  for 
this  type  of  work  is  considerable.  Essentially  all  models  are  built  on 
the  same  principle  although  the  various  features  may  differ  in  regard 
to  completeness  or  design.  They  consist  of  an  illumination  apparatus 
which  guides  the  light  through  the  object,  a  stage  plate 'to  support 
the  object  and  an  observation  system  with  focusing  facilities. 

For  the  selection  of  a  microscope  which  is  to  be  used  for  photo- 
micrography a  few  hints  may  be  of  value : 

The  Illumination  Apparatus 

The  mirror  which  guides  the  light  from  its  source  through  the  con- 
denser should  have  one  plane  and  one  concave  surface.  The  condenser 
should  be  of  the  divisible  type  so  that  the  front  lens  can  be  removed  when 
taking  photos  at  low  magnification.  The  illumination  apparatus  should  be 
equipped  with  an  iris  diaphragm  to  regulate  the  intensity  of  the  light. 
There  should  be  a  rack  and  pinion  movement  to  raise  or  lower  the  con- 
denser. It  is  also  advisable  to  have  the  condenser  mounted  in  a  centering 
adapter.  When  the  photomicrographs  are  taken  at  high  magnification  and 
microscope  lamps  with  concentrated  filaments  are  used  for  this  purpose,  a 
centering  adapter  is  of  essential  importance. 

Object  Stage 

It  is  convenient,  though  not  essential  to  have  a  device  for  the  mechan- 
ical displacement  of  the  specimen.  Such  devices  are  known  as  mechanical 
stages.  They  can  be  obtained  either  separately  or  built  into  the  object  stage. 

Observation  System 

It  has  become  general  practice  to  classify  the  ranges  of  magnification 
as  follows: 


low   power   (requiring  objectives  from  40  to   16mm  focal   length) 
medium  power   (requiring  objectives  from  10-4mm  focal  length) 
high  power  (requiring  objectives  of  less  than  4mm  focal  length). 

For  high  power  microscopy  a  type  of  objective  is  used  which  is  known 
as  immersion  system.  Regarding  further  details  about  objectives  the  reader 
is  referred  to  the  current  literature  of  microscope  manufacturers. 

The  microscope  may  be  equipped  with  a  revolving  nosepiece  accom- 
modating either  two,  three  or  four  objectives.  The  objectives  of  16mm  and 
4mm  are  most  popular.  For  higher  magnifications  oil  immersions  of  about 
2mm  are  generally  used  whereas  for  the  lowest  magnifications  objectives 
of  40mm,  32mm,  24mm  or  thereabout  are  almost  equally  popular. 

Contrary  to  general  opinion  it  is  not  necessary  that  a  microscope  for 
photomicrography  be  equipped  with  a  tube  of  large  diameter.  A  wide  tube 
may  only  be  of  advantage  if  it  is  intended  to  use  a  microscope  for  that  type 
of  photography  (not  photomicrography)  which  the  Leica  user  can  do  with 
the  sliding  focusing  attachment  and  the  regular  Leica  lenses.  In  this  type 
of  work  an  eyepiece  is  not  required. 

It  may  also  be  mentioned  that  it  is  not  advantageous  to  take 
photomicrographs  without  the  eyepiece.  Sometimes  one  meets  with 
the  erroneous  opinion  that  under  such  conditions  sharper  images  can 
be  obtained.  This  is  not  true.  The  apparently  greater  sharpness  is 
simply  due  to  the  lower  magnification.  Actually  such  pictures  lack  in 
sharpness  because  the  objective  is  not  used  at  the  correct  tube-length 
and  thus  a  certain  amount  of  spherical  aberration  is  introduced. 

As  to  the  magnification  of  the  ocular,  it  has  been  mentioned  before 
that  for  general  purposes  an  eyepiece  of  lOx  magnification  is  most 
satisfactory.  Variation  of  magnification  in  the  final  print  can  always 
be  obtained  by  varying  the  ratio  of  enlargement  of  the  negative. 
Only  in  the  case  of  photomicrography  with  the  micro  adapter  ring  an 
eyepiece  of  12x  magnification  may  be  recommended. 

For  Amateur  Photomicrography 

The  rules  given  for  the  selection  of  a  microscope  for  general 
photomicrography  or  that  of  living  object  can  likewise  be  applied  to 
amateur  work.  Only  in  this  latter  case  a  simpler  microscope  will  often 
bo  fully  satisfactory.  In  this  case  it  is  best  to  see  what  the  manu- 
facturer has  to  offer. 

Magnification  and  Resolving  Power 

It  was  explained  at  the  beginning  of  this  chapter  that  the  ob- 
jective of  the  microscope  alone  is  responsible  for  the  revelation  of 
minute  detail  and  that  the  eyepiece  simply  stretches  this  detail  to 
occupy  a  larger  area.  The  power  of  the  objective  to  reveal  detail  is 
called  resolving  power  and  is  limited,  It  is  possible  to  determine  for 
each  objective  the  magnitude  of  the  finest  detail  which  it  is  capable 
of  revealing.  And  since  we  can  also  determine  the  total  magnification 



of  the  image  in  the  negative,  we  are  able  to  find  out  how  much 
space  the  smallest  revealable  detail  will  occupy  in  the  plane  of  the 
negative.  This  information  is  important  because,  as  we  know  from 
the  chapter  about  Leica  lenses,  the  human  eye  can  only  distinguish 
detail  if  it  is  at  least  l/100th  inch  apart  (provided  we  refer  to  detail 
in  a  photograph  which  we  view  from  a  distance  of  10  inches).  Thus 
we  will  finally  be  able  to  answer  the  question:  Plow  much  can  we 
enlarge  the  negative  of  a  photomicrograph  taken  with  the  Leica 
camera  without  creating  the  impression  that  the  enlargement  will 
lack  in  sharpness? 

The  maximum  resolving  power  of  the  objective  can  easily  be 
expressed  quantitatively  by  the  magnitude  of  the  smallest  detail  which 
the  objective  can  resolve.  But  in  practical  photomicrography  this 
maximum  resolving  power  can  seldom  if  ever  be  verified,  because  it 
requires  certain  optical  conditions  for  the  illumination  of  the  object 
which  are  detrimental  in  other  respects.  Therefore  in  practice  the 
obtainable  resolving  power  will  mostly  remain  below  this  maximum 

In  the  books  about  microscopy  we  find  that  the  resolving  power 
depends  upon  the  light  collecting  power  of  the  objective  and  the 
wavelength  of  the  light  with  which  the  specimen  is  illuminated.  The 
light  collecting  power  is  generally  expressed  by  a  term  numerical 
aperture.  Its  meaning  is  not  identical  to  the  relative  aperture  or 
speed  of  a  photographic  lens,  but  has  close  relation  to  it.  We  need 
not  go  into  detail  about  the  correct  interpretation  of  the  term 
numerical  aperture  because  its  actual  magnitude  is  generally  en- 
graved upon  the  mount  of  the  objective  and  is  also  listed  in  the 
catalogs  of  the  manufacturers.  "We  only  have  to  realize  that  the 
higher  the  numerical  aperture  of  an  objective,  the  better  is  its 
resolving  power. 

As  to  the  wavelength  of  the  light,  we  know  that  in  the  spectrum 
of  visible  light,  the  colors  towards  the  violet  end  of  this  rainbow 
have  the  shortest  wavelength.  But  whether  we  can  use  these  rays  for 
the  illumination  of  the  object,  depends  entirely  upon  the  colors  of  its 
structures.  Further  information  about  the  color  of  the  light  to  il- 
luminate the  object  can  be  obtained  in  publications  regarding  the 
application  of  light  filters  for  photomicrography.  For  the  present 
we  must  only  realize  that  the  relation  between  the  resolving  power 
and  -wavelength  of  the  light  is  such  that  an  objective  of  a  certain 
aperture  will  yield  the  best  resolving  power  if  the  wavelength  of 
the  light  which  illuminates  the  object  is  as  short  as  possible. 


But  there  is  a  third  factor  which  influences  the  resolving  power 
and  which  is  often  neglected  in  consideration.  It  refers  to  the  direc- 
tion of  the  light  which  illuminates  the  object.  As  you  know,  the 
intensity  of  the  light  which  passes  through  a  photographic  lens  is 
regulated  by  opening  or  closing  the  iris  diaphragm  with  which  these 
lenses  are  equipped.  In  a  microscopic  objective  there  is  no  iris  dia- 
phragm. But  we  find  this  iris  in  the  substage  of  the  microscope, 
directly  below  the  condenser.  If  we  close  this  iris  diaphragm  the 
object  will  be  illuminated  only  with  a  small  central  beam  of  light. 
By  opening  it,  the  intensity  of  the  illumination  increases.  But  at 
the  same  time  the  resolving  power  of  the  objective  also  increases. 

Still,  the  resolving  power  may  be  increased  without  opening  the 
iris  diaphragm.  We  only  have  to  displace  it  laterally  so  that  the 
small  beam  which  illuminates  the  specimen  will  not  pass  through  it 
centrally,  that  means,  in  the  direction  of  the  optical  axis,  but  obliquely. 

"When  to  increase  the  resolving  power  by  opening  the  iris  and 
when  to  displace  the  iris  laterally  depends  entirely  upon  the  nature 
of  the  structures  of  the  specimen  and  upon  the  quality  of  the  objec- 
tive. An  objective  of  good  quality  can  be  used  with  the  iris  diaphragm 
comparatively  far  open  whereas  in  an  objective  of  inferior  quality 
those  misbehaviors  of  light  about  which  we  learned  in  the  chapter  on 
lenses  will  make  themselves  felt  too  much. 

By  opening  the  iris  diaphragm  we  render  the  illumination  more 
diffuse  and  there  may  be  detail  which  with  such  illumination  will  be 
obliterated.  The  surface  of  a  piece  of  paper  may  appear  smooth  in 
diffuse  light,  but  hold  it  in  the  beam  of  a  powerful  searchlight  so  that 
the  direction  of  this  light  meets  the  paper  surface  at  grazing  inci- 
dence, very  obliquely.  Every  little  unevenness  in  the  surface  will 
throw  a  deep  shadow  and  the  little  hills  and  valleys  will  appear  most 

These  few  remarks  should  indicate  that  the  method  of  illumina- 
tion has  a  great  influence,  not  only  upon  the  visibility  of  detail  which 
may  be  so  small  that  the  highest  possible  resolving  power  is  necessary 
to  reveal  it,  but  also  because  this  detail  may  be  of  such  shape  or  nature 
that  special  tricks  must  be  applied  to  render  them  visible  even  if  they 
are  large  enough  to  require  only  little  resolving  power. 

To  summarize  we  may  say  that  under  normal  conditions  the  iris 
diaphragm  of  the  substage  should  rarely  be  opened  more  than  14  to  i/> 
of  its  greatest  opening  and  as  to  the  color  of  the  light  we  shall  learn 
presently  why  a  green  filter  will  find  most  frequent  application. 
Under  such  conditions  it  is  safe  to  assume  that  the  magnification  re- 



quired  to  separate  the  detail  until  it  is  about  l/100th  inch  apart,  is 
about  equal  to  600  times  the  value  of  the  numerical  aperture  of  the 
objective  used. 

From  the  catalogs  of  the  manufacturers  we  learn  the  initial  mag- 
nifications and  numerical  apertures  of  the  current  objectives.  We 
know  that  the  eyepiece  lOx  yields  about  1/3  of  its  full  magnifying 
power  when  used  with  the  Leica  camera  as  described  before  and  with 
this  information  on  hand  we  can  determine  how  much  the  Leica 
negative  of  a  photomicrograph  can  be  magnified  without  losing  the 
aspect  of  a  sharp  picture.  The  following  table  contains  these  values 
for  some  of  the  most  popular  objectives  and  may  be  of  help  in  photo- 

This  table  has  been  prepared  for  Leitz  objectives  but  by  com- 
paring the  figures  for  focal  length,  initial  magnification  and  numerical 
aperture  with  those  constants  of  the  objectives  of  other  manufacturers 
it  will  become  evident  that  the  figures  can  be  helpful  also  to  users  of 
other  objectives. 

Type  of 










(oil  immersion) 
(oil  immersion) 
(oil  immersion) 








Initial  Mag- 
nification of  Numerical 
objective       Aperture 


6    x 

10    x 
12    x 

14    x 


45    x 

46    x 

65    x 

100    x 

92    x 

92    x 






cation on 



33  x 
40  x 


66  x 

150  x 

153  x 

216  x 

333  x 

306  x 

306  x 


possible  to 


detail  1/100" 

4.6  x 

6.3  x 

6.0  x 
4.5  x 

4.5  x 

5.1  x 

4.1  x 

5.5  x 

3.4  x 
3.8  x 

2.6  x 

Thus  we  should  conclude  our  chapter  on  photomicrography  be- 
cause the  problems  pertaining  specifically  to  the  miniature  camera 
have  been  covered.  But  there  are  so  many  questions  pertaining  to 


microscopy  which  the  miniature  camera  owner  would  like  to  have 
answered  that  at  least  some  of  them  shall  be  briefly  discussed. 

Light  Sources 

It  is  difficult  to  recommend  one  definite  light  source  because  so 
many  different  types  are  suitable  and  yet  each  of  them  has  special 
advantages,  depending  upon  the  work  which  has  to  be  done. 

For  photomicrography  of  living  objects,  for  instance,  a  great 
deal  of  light  is  required  because  the  image  is  formed  only  by  that 
small  portion  which  is  reflected  from  the  surfaces  of  the  object.  The 
effective  intensity  of  light  sources  for  microscopy,  however,  is  not 
measured  in  terms  of  total  candlepower  and  it  is  very  important 
for  the  microscopist  to  understand  why  we  need  another  measure. 
Actually  we  can  compare  the  power  of  microscope  lamps  only  in 
regard  to  their  intrinsic  intensities.  This  will  become  evident  if  we 
compare  a  lamp  for  110  volts  and  550  watts  with  one  for  6  volts  and 
30  watts.  The  only  difference  is  to  be  found  in  the  length  of  the 
filament,  that  of  the  lamp  for  110  volts  being  about  18  times  as  long 
as  that  of  the  lamp  for  6  volts.  In  both  cases,  however,  the  filament 
is  fed  by  a  current  of  5  amperes  and  pieces  of  equal  length  of  the 
two  filaments  emit  the  same  amounts  of  light.  Of  course  with  the 
110  volt  lamp  we  could  illuminate  an  area  having  18  times  the  square 
contents  of  that  which,  with  the  same  condenser  system  the  6  volt 
lamp  will  illuminate.  But  the  condenser  systems  are  designed  for 
rather  small  light  emitting  units  because  it  happens  that  among  these 
we  find  the  light  sources  of  greatest  intrinsic  intensity. 

Of  the  two  light  sources  mentioned  above  the  one  for  6  volts  should 
of  course  be  preferred  because,  although  it  offers  the  same  intrinsic 
and  therefore  effective  intensity,  it  consumes  only  1/lSth  of  the  amount 
of  energy.  The  fact  that  these  lamps  must  be  used  with  a  transformer 
(or  a  rheostat,  if  d.  e.  is  available)  should  not  be  considered  as  a  dis- 
advantage because  the  lamp  fulfills  an  optical  purpose  and  its  per- 
formance in  this  respect  is  the  only  important  thing. 

The  intrinsic  intensity  of  a  light  source  increases  in  proportion 
to  the  temperature  of  the  light  emitting  area.  A  filament,  heated  to 
incandescence  can  never  become  as  hot  as,  for  instance  the  crater  of 
an  arc  lamp  where  the  carbon  is  heated  beyond  the  point  of  incan- 
descence so  that  it  is  actually  consumed  Arc  lamps  have  a  compara- 
tively small  sized  crater  and  in  order  to  t^able  the  miscroscopist  to 
take  full  advantage  of  this  important  type  of  lamp,  the  condenser 
systems  of  microscopes  are  so  arranged  that  this  small  light  emitting 
unit  will  illuminate  the  entire  field  under  observation.  These  arc 



lamps  are  often  the  only  type  of  light  source  which  will  make  in- 
stantaneous photomicrography  of  opaque  living  objects  possible,  even 
with  the  small  Leica. 

For  photomicrography  in  transmitted  light  we  may  not  require 
these  strong  light  sources.  In  the  first  place,  the  entire  amount  of 
light  which  is  concentrated  by  the  condenser,  passes  through  the 
microscope  and  is  only  partly  absorbed  by  the  structures  of  the  object 
which  in  the  photograph  will  appear  darker  than  the  background. 
Furthermore,  these  objects  are  generally  not  moving  and  longer  ex- 
posures are  permissible.  In  these  cases  a  regular  desk  lamp  with  an 
inside  frosted  bulb,  possibly  a  photoflood  bulb,  will  give  satisfactory 
illumination.  Clear  glass  bulbs,  showing  the  filament,  should  not  be 
used,  unless  a  ground  glass  is  interposed. 

It  is  not  possible  to  explain  here,  how,  for  every  magnification, 
uniform  illumination  can  be  obtained.  The  reader  must  try  to  obtain 
such  information  from  microscope  manufacturers  or  text  books.  He 
will  find,  that  by  following  definite  rules  he  can  avoid  the  rather  uncer- 
tain method  of  trial  and  error,  but  these  methods  would  require  too 
much  space  in  this  chapter. 

Light  Filters 

The  application  of  light  filters  in  photomicrography  is  another 
problem  which  requires  thorough  study.  The  reader  is  referred  to 
current  literature.  The  Eastman  Kodak  Co.  published  a  booklet,  en- 
titled '' Photomicrography ' ?  from  which  valuable  information  can  be 

In  the  vast  majority  of  cases  where  stained  preparations  are  to 
be  photographed,  a  green  filter,  such  as  the  Wratten  B  filter  will  be  of 
great  help.  Not  only  are  most  of  the  stains,  used  in  practice,  of  such 
color  that  a  green  filter  will  produce  the  best  contrast  and  differentia- 
tion, but  the  light  transmitted  by  this  filter  is  of  that  range  of  wave- 
lengths for  which  the  correction  of  microscope  objectives  is  most 

As  to  the  best  place  to  insert  the  filter,  no  special  advice  is 
necessary  since  it  can  be  inserted  at  any  place  between  the  lamp  and 
the  microscope.  It  may  happen  however,  that  the  filter  is  at  a  place 
where  any  dust  spots  or  impurities  on  its  surface  would  show  in  the 
field  under  observation  because  the  condenser  may  form  an  image  of 
the  filter  in  the  plane  of  the  object.  If  such  dark  spots  are  visible, 
it  is  easy  to  find  out  whether  they  are  produced  by  the  filter  or  by 
impurities  on  the  lenses  of  the  eyepiece.  Suppose  we  move  the  filter 
laterally  and  the  spots  follow  the  motion,  they  are  caused  by  dust  on 


the  surface  of  the  filter.  But  if,  upon  rotation  of  the  eyepiece  in  the 
microscope  tube,  the  spots  follow  this  rotation,  they  are  due  to  impuri- 
ties on  the  lenses  of  the  ocular.  In  both  cases,  the  surfaces  should  be 
cleaned,  but  if  the  filter  gave  the  cause,  it  can  also  be  moved  closer  to 
the  condenser. 


In  photomicrography  it  is  often  not  necessary  and  even  detri- 
mental to  use  panchromatic  film  of  high  sensitiveness.  The  panchro- 
matism  of  the  film  is  not  required  when  a  green  filter  is  used.  As  you 
know,  the  only  difference  between  orthochromatic  and  panchromatic 
film,  lies  in  fact  that  the  latter  is  also  sensitive  to  red  light.  But  if 
the  filter  has  prevented  all  red  light  from  passing  through  the  micro- 
scope, this  extra  sensitiveness  is  of  no  value.  On  the  other  hand, 
panchromatic  films  are  generally  less  sensitive  for  greem  light  (that  is 
why  green  safelights  can  be  used  in  the  darkroom  for  their  develop- 
ment) so  that  their  general  high  speed  does  not  exist  for  that  range  of 
light  color  which  is  transmitted  by  the  filter. 

Finally  we  must  realize  that  these  superspeed  films  really  do  not 
yield  that  same  fine  detail  which  we  obtain  with  slower  films.  It  is 
true  that  the  development  can  hold  the  grain  size  down  but  for  reasons 
which  are  too  involved  to  permit  explanation  at  this  place,  it  is  really 
true  that  the  slower  films  with  inherently  finer  grain  produce  finer 

To  sum  up,  any  modern  orthochromatic  film  is  perhaps  most  suit- 
able for  photomicrography.  Where  speed  is  essential,  the  faster  emul- 
sions are  to  be  preferred,  where  detail  rendition  is  of  primary  im- 
portance, the  slower  emulsions  are  better.  Only  in  cases  where  living 
objects  are  photographed  with  the  Ultropak  or  a  darkfield  condenser 
and  if  in  these  cases  no  filter  is  used,  a  fast  panchromatic  film  will 
have  its  place. 

In  exceptional  cases  positive  film  may  be  used.  But  we  must  not 
forget  that  this  film  is  not  sensitive  to  green  light.  Used  when  the 
Wratten  B  filter  has  been  interposed  in  the  course  of  rays,  a  photo- 
micrograph on  positive  film  would  only  yield  a  blank  space.  Without 
a  filter,  the  positive  film  in  itself  will  perform  what  a  blue  filter  would 
have  done  with  orthochromatic  film.  This  fact  may  be  helpful  in 
photomicrography  of  diatoms  where  the  utmost  in  detail  rendition  is 
aimed  for.  But  this  task  is  perhaps  one  of  the  very  few,  where  the 
miniature  camera  actually  does  not  offer  anything  but  disadvantages 
over  the  larger  size  cameras. 




Help  in  gauging  the  exposure  for  a  photomicrograph  is  perhaps 
most  urgently  needed  and  it  is  unfortunate  that  just  in  this  respect  it 
can  hardly  be  given.  The  exposure  depends  upon  too  many  different 
factors.  There  is  the  intrinsic  intensity  of  the  lamp,  the  size  of  the 
filament,  the  opening  of  the  iris  diaphragm  in  the  substage,  the  magnifi- 
cation of  objective  and  eyepiece,  the  numerical  aperture  of  the  objec- 
tive, the  color  of  the  light  filter,  the  density  of  the  specimen,  the  sensi- 
tiveness of  the  film  to  the  color  which  the  filter  transmits  and  there 
are  many  other  factors. 

The  best  way  out  of  the  difficulty  is  to  take  test  photos  under 
standard  conditions,  varying  the  actual  time  of  exposure.  After 
development  of  a  test  film  and  if  the  exact  data  for  each  exposure  have 
been  recorded,  the  correct  time  can  easily  be  determined. 

Place  the  light  source  at  a  definite  distance  from  the  microscope, 
select  the  filter,  record  the  position  of  the  iris  diaphragm  in  the  sub- 
stage  of  the  microscope,  the  magnification  and  numerical  aperture  of 
the  objective,  the  color  and  density  of  the  specimen,  the  magnifying 
power  of  the  eyepiece,  the  type  of  film  used  and  then  take  several 
exposures,  varying  the  time  in  wide  limits.  You  can  easily  find  the  best 
negative.  Now  maintain  these  standard  conditions  for  this  objective 
and  only  if  a  specimen  of  great  density  is  under  observation,  lengthen 
the  exposure.  Of  course,  if  a  different  filter  is  used,  new  tests  have 
to  be  made,  unless  you  know  the  relative  filter  factor  for  the  particular 
film  brand  used. 

This  standardization  will  undoubtedly  be  the  shortest  way  to 
success  and  since  a  microscope  equipment  will  generally  not  contain 
more  than  three  or  four  objectives  and,  at  the  most  two  or  three  filters, 
the  work  involved  is  really  negligible,  not  to  speak  of  the  value  of 
having  gone  through  an  experience  of  this  type. 


Fig.  244     Dental  Operating-  Room  of  A.  Laurence  Dunn,  D.  D.  S.,  Santa 
Barbara,  California.    Photographed  by  J.  Walter  Collinge 

(Dr.  Dunn  is  left-handed  and  the  equipment  is  arranged  accordingly) 




Dentistry  offers  one  of  the  finest  fields  for.  the  Leica  camera  in 
scientific  work.  "With  it  the  general  practitioner,  the  specialist,  and 
the  research  worker  alike  will  find  the  opportunity  to  make  records 
of  a  remarkable  quality. 

To  show  the  many  uses  in  dentistry  and  in  photography  of  all 
small  objects,  and  to  explain  how  the  pictures  may  be  obtained  with 
a  minimum  of  trouble,  a  simplified  yet  highly  efficient  technique  is  be- 
ing offered.  The  work  is  divided  into  three  sections  dealing  first  with 
the  equipment  necessary,  second  the  photography  itself,  and  third  a 
system  of  records. 

Equipment  Required 

1.  Leica  camera  of  any  of  the  later  models,  and  one  of  the 
50  mm  lenses  such   as  the  Elmar  f:3.5,   Hektor  f:2.5,  or 
Summar  f  :2  and  a  cable  release. 

2.  Fuldy  sliding  focusing  copy  attachment. 

3.  Camera  support  and  reflecting  board. 

4.  Magnifying  viewer. 

5.  Two  extension  tubes,  12mm  and  22mm. 

6.  Photoflood  lamp  in  reflector. 

7.  Leicameter. 

8.  Yard  stick. 

9.  Cardboard  backgrounds  (black,  gray,  white,  etc.). 
10.    Eeeord  pad  and  pencil. 

One  piece  of  apparatus  that  greatly  simplifies  photography  at  the  dental 
chair  is  the  camera  support,  a  home-made  device.  The  one  shown  in  figure 
245  may  serve  as  a  suggestion  of  what  can  be  constructed  to  meet  individ- 
ual needs.  Roughly,  it  consists  of  a  pipe  welded  onto  an  old  automobile  fly- 
wheel. Being  mounted  on  casters,  it  is  moved  easily,  yet  stays  in  position 
solidly.  It  is  rolled  in  place  by  hand  and  minor  adjustments  for  position  are 
made  by  foot,  with  one  foot  on  the  base. 

As  the  photograph  shows,  the  apparatus  is  adjustable  for  every  height 
and  position.  The  horizontal  arm  can  slide  freely  on  the  upright  pipe  and  is 
controlled  by  a  thumb  screw. 

To  overcome  vibration  there  are  three  upright  rods  welded  both  to  the 
flywheel  and  the  upright  pipe.  The  reflecting  board  is  made  of  an  aluminum 


Fig.  245  Home-made  Port- 
able Camera  Stand  sup- 
porting Leica  camera  with 
Sliding  Focusing  Attach- 
ment and  Eeflector.  The 
outfit  is  readily  available 
for  use  at  the  dental 
chair.  Both  Camera  and 
Reflector  are  easily  ad- 
justable, providing-  excep- 
tional flexibility  and  ri- 

cookie  sheet.  One  side  of  it  is  kept  with  a  high  polish  for  strong  reflections 
while  the  other  is  dulled  slightly  by  a  very  fine  sand  paper  or  by  sand 

The  camera  is  attached  to  the  horizontal  arm  by  a  Leica  Ball  Jointed 
Tripod  head.  I  have  found  nothing  that  will  take  the  place  of  this  device  in 
holding  the  camera  solidly  in  all  positions.  Figure  245  shows  the  construc- 
tion of  the  entire  support.  It  can  be  made  very  simply  and  inexpensively. 
The  Fuldy  copying  attachment  is  described  on  page  189.  It  is  the  ideal 
piece  of  apparatus  for  accurate  viewing  and  focusing  in  close  work.  The 
proposed  image  is  seen  very  clearly  on  the  ground  glass  back.  However,  for 
the  most  careful  focusing,  I  strongly  urge  the  addition  of  the  5x  magnifier 
and  viewer. 


Dental  Photography 

For  close-up  work  at  least  one  and  preferably  two  extension  tubes  are 
needed.  A  serviceable  arrangement  is  to  have  the  12mm  and  the  22mm 

Needless  to  say,  the  Weston  Leicameter  is  indispensable.  To  attempt 
to  photograph  numerous  objects  under  varying  light  conditions  is  too  hazard- 
ous without  some  means  of  measuring  the  light  value  scientifically. 

The  Photoflood  lamp  should  be  mounted  in  some  handy  holder  and 
reflector.  If  possible  it  should  be  set  up  close  by,  to  be  swung  into  position 
on  a  moment's  notice.  At  least  one  spare  bulb  should  be  in  reserve  at  all 
times.  One  ingenious  way  of  saving  the  Photoflood,  which  burns  only  two 
hours,  is  to  wire  it  through  a  Leitz  Illumination  Control  which  has  seven 
degrees  of  measured  light  intensity  (see  page  159).  Thus  the  light  can  be 
reduced  to  mild  brightness  for  focusing  and  brought  to  the  desired  degree 
of  intensity  for  the  actual  exposure. 

Finally,  with  a  yardstick,  pencil,  and  the  record  pad  described  in  the 
third  section  of  this  chapter  the  equipment  is  ready  for  use. 

A  picture  of  the  apparatus  set  in  position  is  shown  in  figure  244.  When 
not  in  use  the  outfit  is  pushed  back  to  the  wall  and  the  lamp  swung  to 
the  side  of  the  unit.  Notice  particularly  how  the  camera  support  with  its 
camera  and  reflecting  board,  and  the  lamp,  are  all  adjusted  in  working 
position  with  no  interference  to  the  operator.  For  work  in  the  laboratory 
or  elsewhere  in  the  room  the  camera  support  can  easily  be  rolled  into  any 
position  desired. 

Making  the  Photographs 

To  illustrate  the  diversity  of  uses  of  photography  in  dentistry 
we  start  first  with  a  series  of  pictures  at  the  chair,  then  a  series  taken 
in  the  laboratory,  in  research,  and  in  the  preparation  of  papers  or 
clinics.  Many  of  the  ideas  presented  in  this  chapter  apply  equally 
well  to  medicine  and  surgery  and  to  the  photography  of  all  small 

The  largest  object  photographed  at  the  chair  is  the  patient's 
face,  both  front  view  and  profile.  This  provides  a  general  record,  par- 
ticularly where  any  change  is  to  be  made  in  the  front  of  the  month. 
The  main  uses  are  in  the  young  and  the  old,  the  children  needing 
orthodontia  and  the  elderly  patients  requiring  full  dentures.  Such 
a  picture  will  give  an  accurate  record  of  the  conditions  to  be  repro- 
duced or  eliminated  and  will  serve  as  a  means  of  comparing  the 
finished  results  with  the  original.  Moreover,  I  feel  it  to  be  a  very 
wise  procedure,  in  this  age  when  so  many  faces  are  disfigured  in  auto- 
mobile accidents,  to  take  full  face  and  profile  photographs  of  all 

For  these  pictures  the  ideal  distance  of  the  camera  from  the  subject  is 
twenty-two  inches. 

In  most  offices  the  full  face  picture  (fig.  246)  can  be  taken  without 
electric  illumination,  daylight  being  sufficient.  Formerly,  I  used  one  Photo- 
flood  with  a  reflecting  board  but  now  seldom  use  either  in  the  full  face 
picture.  In  the  profile,  help  the  lighting  with  one  Photoflood  and  use  a  black 


cardboard  to  serve  as  a  background  (fig.  247).  Whenever  using  the  aluminum 
reflecting  board,  adjust  first  the  Photoflood  light  and  then  the  reflecting 
board.  Place  the  latter  in  position  to  reflect  the  rays  from  the  Photoflood  so 
that  this  secondary  illumination  will  brighten  the  surfaces  not  struck  directly 
by  the  Photoflood.  The  technique  of  adjusting  the  board  is  exactly  the  same 
that  a  small  boy  uses  in  annoying  the  neighbors  with  a  penny  mirror  on  a 
sunny  day. 

Fig.  246  (left)  Full  face 
view,  made  with  Fuldy 
C.  A.  at  22",  one  second 
at  f  :18 



Fig.    247      Profile,    same 
case,  data  as  above 

The  Fuldy  copying  attachment  is  indispensable  for  work  in  dentistry 
and  close-up  photography.  In  using  the  Fuldy  copying  attachment  at  a 
distance  beyond  37%  inches,  difficulty  will  be  encountered  from  interference 
of  the  collapsible  lens  mount.  This  can  be  overcome  as  follows:  With  the 
focus  lever  set  at  infinity,  work  the  lens  into  precise  focus  by  sliding  it  in 
and  out.  Then  swing  the  focus  lever  down  to  the  opposite  limit,  3.5  for 
instance.  Next  slide  the  camera  across,  swing  the  lever  back  to  infinity, 
and  all  will  be  in  proper  focus  and  adjustment. 

The  next  closest  picture  is  that  of  the  anterior  teeth  (figs.  248- 
251).  For  this  put  on  the  12mm  extension  tube  and  bring;  the 
camera  up  to  approximately  nine  and  a  half  inches.  The  distance 
from  the  subject  always  means  the  distance  measured  from  the  sub- 
ject to  the  back  of  the  camera  or  the  film,  and  not  to  the  lens.  In 
this  and  closer  work  on  patients  the  Photoflood  should  be  used.  Fig- 
ure 248  shows  a  picture  in  stronger  lights  and  shadows,  while  figure 
249  smoother  lighting  and  less  contrast. 

A  handy  retracting  device  is  shown  in  figures  249,  250  and  251.  It  is 
first  formed  as  desired  in  wax  and  then  converted  into  vulcanite.  The 
method  of  use  for  the  molar  region  is  shown  in  figure  251. 

Finally  where  a  single  tooth,  or  a  group  of  two  or  three  is  desired, 
use  the  12  mm  and  the  22  mm  together,  obtaining  a  34  mm  extension 
tube.  Place  the  camera  approximately  eight  and  one-half  inches  from  the 
subject.  Study  pages  198-199  on  the  decrease  in  light  value  with  the  use  of 
extension  tubes  and  plan  your  timing  accordingly. 


Dental  Photography 

Focusing  for  Close-Up  Objects 

Figure  252  is  an  example  of  close-up  photography.  Notice  not  only 
the  form  and  detail  of  the  tooth  as  reproduced  here,  but  also  the  bit 
of  gauze  pressed  against  the  right  central  incisor.  Here  is  an  exam- 
ple of  how  a  great  deal  of  time  and  tension  can  be  saved  in  the  care- 
ful focusing  for  close-up  work.  First  cut  a  small  square  of  gauze 

Fig.  248     22mm  Tube  at  9  %",  one 
second  at  f:12.5 

Fig.  249     22mm  Tube  at   9' 
second  at  f  :18 

from  a  dental  napkin  or  other  loose  fabric  material.  Next  select  that 
position  of  the  field  most  desired  to  be  in  accurate  focus.  If  the  field 
is  flat  it  will  be  simpler.  If  it  has  considerable  depth,  as  in  figure  266 
and  you  have  computed  what  can  be  gotten  into  focus,  locate  a  spot 

Fig.  250    22mm  Tube  at  9%",  half 
second  at  f:6.3    (overexposed) 

251     12mm  Tube  at  12",  one 
second  at  f  :18 

which  will  be  two-fifths  of  the  way  from  the  front  limit  toward  the 
back  limit.  Place  the  square  of  gauze  on  the  selected  spot,  wherever 
it  may  be,  and  focus  on  the  gauze  instead  of  any  other  object  in  the 
field.  You  will  then  be  focusing  on  a  hair-line  instead  of  a  flat 

The  preceding  pictures  have  shown  how  the  field  can  be  pro- 
gressively diminished  and  the  size  of  the  teeth  relatively  increased. 
Study  the  usual  attachments,  distances  and  lighting  for  each  type  of 


picture,  and  with  but  little  practice  you  will  soon  develop  a  standard 
routine  for  each. 

Tronsillummation  of  Teeth 

Figures  253  and  254  show  the  effect  of  transillumination  of  an 
anterior  tooth.  Here  we  are  confronted  with  the  double  problem  of 
two  lighting  systems  in  use  simultaneously.  This  should  not  be  at- 
tempted until  you  have  established  a  standard  system  of  lighting 
for  your  own  office  which  will  give  you  results  such  as  in  figures 
249  and  252.  When  that  has  been  worked  out  to  your  satisfaction 

Fig.  252     12  and  22mm  Tubes  at 
8%",  one  second  at  f  :18 

you  are  ready  to  run  a  series  to  determine  the  correct  strength  for  the 
trans-illuminating  light.  First,  reduce  the  main  or  standard  lighting 
approximately  30  per  cent  below  normal.  I  use  the  Eitter  transillu- 
minating  lamp  of  the  antrum  type,  as  pictured  in  figure  268.  Adjust 
it  so  that  it  has  mild  brightness  and  place  it  as  shown,  behind  the 

Fig.  253     12mm  Tube  at  17",  half 
second  at  f  :18 

Fig.  254    22mm  Tube  at  9%",  one 
second  at  f  :18 

tooth.  Eecord  all  factors,  and  particularly  the  number  shown  on  the 
Eitter  rheostat.  Then  photograph.  Next  increase  the  light  of  the 
Eitter  lamp  by  one  point  and  take  the  next  picture.  Keep  increasing 
the  voltage  one  point  at  a  time  for  approximately  five  pictures,  being 
certain  to  keep  accurate  records.  From  the  finished  results  you  can 
select  the  one  which  is  to  serve  as  your  standard  for  future  pictures. 


Dental  Photography 

The  next  two  pictures,  figures  255  and  256  are  also  examples  of  double 
lighting,  although  in  these  cases  the  transilluxninating  light  is  not  shining 
through  the  teeth  to  be  operated  but  onto  them,  a  distant  view  and  a 
close-up.  Here  again  the  same  routine  must  be  worked  out  as  in  the  pre- 
ceding paragraph,  a  series  run  to  determine  the  correct  balance  of  lights. 

The  main  thing  to  bear  in  mind  here  is  that  it  must  be  the  Hitter  light 
and  not  the  standard  light  that  has  the  correct  brilliance.  In  other  words, 
the  transilluminating  light  must  be  such  that  it  will  neither  over-expose  nor 
under-expose  the  negative,  while  the  standard  lighting  must  definitely  under- 
expose. ^  And  let  me  save  time  and  money  for  you  by  again  repeating  that 
effects  like  these  can  be  obtained  only  by  running  a  series  of  exposures  and 
keeping  records. 

Fig.  255     12mm  Tube  at 
second  at  f  :5.6 


Fig.    256     22mm    Tube    at    10%'' 
half  second  at  f  :18 

The  extent  to  which  the  depth  of  focus  can  be  increased  by  stopping 
down  to  a  small  aperture  is  shown  in  figures  253  and  255.  The  former  was 
taken  with  the  diaphragm  closed  to  f  :18,  while  the  latter  was  opened  to 
f:5.6.  Notice  particularly  the  clearness  of  the  fingers.  It  is  because  of 
the  increase  of  precise  focusing  on  unimportant  details  that  I  prefer  to 
close  the  aperture  as  much  as  possible.  Having  selected  18  as  my  standard 
aperture  for  most  work,  I  can  focus  through  the  Fuldy  attachment  with 
the  diaphragm  wide  open  at  3.5,  then  swing  the  lever  to  the  opposite  ex- 
treme, or  18,  entirely  by  the  sense  of  touch.  Eliminating  the  necessity  of 
getting  around  and  viewing  the  diaphragm  reading  in  close  quarters  is  a 
great  convenience,  and  obtaining  greater  depth  of  focus  is  an  advantage  not 
to  be  overlooked. 

Photographing  Reflected  Images 

Another  variation  from  the  usual  photograph  is  the  one  taken 
in  the  mirror.  Figures  257  and  258  are  two  examples.  The  first  is  a 
picture  of  the  entire  vault  of  the  mouth,  with  an  inflamed  mucosa 
irritated  by  a  full  vulcanite  denture.  The  second  shows  a  tooth  fol- 
lowing the  treatment  of  pyorrhea  by  the  stirgieal  method.  There  are 
two  precautions  for  this  type  of  picture.  First,  the  lighting  must  be 
studied  very  carefully  to  make  sure  that  the  area  reflected  in  the 
mirror  is  as  well  illuminated  as  the  surrounding  non-reflected  areas. 
It  is  the  latter  rather  than  the  former  that  will  determine  the  light 
value  'reading,  so  be  careful.  Second,  the  focusing  must  be  done  on 


the  reflected  image.  It  must  not  be  done  on  the  non-reflected  front 
surface  of  the  object,  nor  on  the  glass  of  the  mirror,  but  on  the  image 
shown  in  the  mirror.  With  careful  holding  of  the  mirror  this  can 
be  done  as  accurately  as  in  the  usual  pictures. 

Fig.  257     12mm  Tube  at  10",  half 
second  at  f  :18 

Fig.  258    22mm  Tube  at  9%",  one 
second  at  f  :18 

There  is  nothing  that  will  take  the  place  of  the  photograph  in 
explaining  the  technique  of  many  operations.  Where  subject  matter 
is  being  prepared  for  lecture  or  publication,  visual  education  should 
be  the  first  considered.  An  example  of  this  is  shown  in  the  two  pic- 
tures, figures  259  and  260,  where  a  fixed  bridge  is  being  seated  with  a 
rubber  dam  in  position,  showing  the  case  before  and  after  the 

Fig.  259     12mm  Tube  at  13",  one 
second  at  f  :18 

Fig.  260     12mm  Tube  at  13",  one 
second  at  f  :18 

In  figure  261  an  interesting  method  of  eliminating  background 
shadows  is  shown.  Apparently  the  vulcanite  bridge,  a  Dunn  Tempo- 
rary Bridge,  is  suspended  in  mid-air.  The  effect  is  obtained  by  sup- 
porting the  object  on  plate  glass  and  placing  the  cardboard  back- 
ground six  inches  or  more  below  the  glass. 

At  this  point  it  might  be  well  to  refer  to  backgrounds.  Strong 
cardboards  should  be  on  hand  for  use  at.  all  times,  including  black, 
dark  gray,  light  gray,  and  white  surfaces.  Often  the  background 


Dental  Photography 

proves  to  be  the  salvation  of  the  picture,  especially  with  the  smaller 

Other  types  of  cases  are  illustrated  in  succeeding  pictures.  An  unusual 
emergency  denture  repair  is  pictured  in  figure  262.  Here  the  points  of  sig- 
nificance from  a  photographic  standpoint  are  the  reproduction  of  the  round- 
ness of  the  porcelain  teeth,  obtained  by  a  proper  lighting,  and  the  great 
depth  of  field,  obtained  by  stopping  down  to  a  small  diaphragm  and  timing 

Figure  263  illustrates  how  photography  is  an  aid  in  the  instruc- 
tion of  cavity  preparation.  Figure  264  shows  plaster  models  of  a  case 
before  and  after  orthodontic  treatment. 

Fig.  261     12mm  Tube  at  9",  four  Fig.  262     22mm  Tube  at  10",  four 

seconds  at  f  :18  seconds  at  f  :18 

Determining  Exposures 

Figure  250  shows  the  result  of  a  mistake  that  is  apt  to  be  made 
very  commonly  in  this  type  of  work,  that  of  over-exposure.  Recognize 
in  measuring  the  light  value  in  these  cases  that  the  teeth  form  a  very 
small  part  of  the  face  and  are  much  lighter  than  the  rest  of  the  face. 
For  it  is  not  the  teeth  so  much  as  the  skin  that  determines  the  Leica- 
meter  reading.  If  a  photograph  is  made,  based  on  the  Leicameter 

Fig.  263     12mm  Tube  at  12",.  two  Fig.  264     12mm  Tube  at  17",  two 

seconds  at  f:18  seconds  at  f:18 

reading  obtained  directly,  it  will  be  flat  and  burned  up,  as  shown  in 
figure  250.     If  the  time  is  cut  considerably  the  result  will  be  as  in 


figures  248  and  249.  Another  suggestion  regarding  this  is  told  in 
connection  with  figure  264. 

One  is  likely  to  be  deceived  as  to  the  true  light  value  of  small 
objects,  particularly  where  they  are  very  light  in  color.  This  is  well 
demonstrated  in  the  ease  of  these  three  plaster  models.  Placed  on 
a  black  background,  the  greatest  light  value  they  would  record  was 
slightly  toward  0  from  1.  With  the  Leicameter  set  for  a  film  with 
a  speed  of  23,  the  correct  camera  adjustments  were  shown  to  be  13 
seconds  at  aperture  18.  However,  this  was  felt  to  be  far  beyond 
the  correct  timing. 

To  determine  the  correct  exposure  a  large  white  card  of  approxi- 
mately the  same  degree  of  brilliance  as  the  plaster  was  held  in  place 
just  in  front  of  the  models  and  a  reading  taken  of  the  card.  Instead 
of  slightly  less  than  one,  the  light  value  now  proved  to  be  1/6  and 
the  adjustments  this  time  were  changed  from  13  seconds  at  18,  to 
V/%  seconds  at  18.  The  picture  as  shown  was  made  with  the  latter 

In  your  initial  work  on  each  new  type  of  case,  you  will  save 
time  by  running  a  series  of  pictures,  all  of  the  same  subject.  For 
instance,  figure  263  was  obtained  first  by  finding  that  the  light  value 
was  probably  1/6.  Then  a  small  diaphragm,  f  :18,  was  chosen  in  order 
to  have  maLximum  depth  of  focus.  Finally  a  series  was  run  starting  at 

1  second,  then  2,  3,  4,  5,  and  ending  with  6  seconds,  but  without  the 
series  of  pictures  I  could  not  have  been  certain.    As  originally  com- 
puted with  the  aid  of  the  Leicameter  reading  of  the  white  card,  the 

2  second  exposure  proved  to  be  ideal.    Again  let  me  urge  you  always 
to  run  a  series  of  exposures  in  undertaking  a  new  type  of  work,  then 
select  the  best  and  use  that  as  standard  from  then  on. 

Occasionally  there  will  be  a  case  where  the  arranging  of  objects 
and  studying  their  most  desirable  positions  is  difficult.  All  of  the 
plaster  models  were  such  examples.  The  slight  turning  of  one  would 
throw  certain  lines  in  and  others  out,  and  the  reduced  image  as 
dewed  on  the  ground  glass  of  the  Fuldy  attachment  made  adjust- 
ment difficult.  In  such  a  case  place  the  object  in  general  focus  and 
approximate  arrangement,  then  slip  the  camera  off  of  the  copy  at- 
tachment, quickly  unscrew  the  lens  and  you  have  an  open  hole 
through  which  to  view.  Using  it  as  a  frame  for  your  picture,  do  the 
final  arranging  of  the  object,  then  replace  the  lens  and  camera  and 
complete  the  photography.  This  aid  is  seldom  needed  but  can  be  of 
great  help  in  studying  arrangement  in  difficult  cases. 

Research  work  can  be  recorded  as  shown  in  figure  265,  representing-  a 
steel  die  and  brass  tube  testing  the  precision  of  a  gold  casting,  and  again 


Dental  Photography 

in  figure  266,  a  human  jaw  showing  a  deep  pyorrhea  pocket  (indicated  by 
the  arrow),  and  the  effect  of  occlusal  attrition. 

Other  objects  which  can  be  photographed  are  such  things  as  radio- 
graphs (fig.  267),  collections  of  interesting  dental  appliances,  the  oper- 
ator's hand  demonstrating  a  certain  technique  (fig.  268),  and  so  forth. 

Fig.  265  Hollenbeck  Tube  Dies. 
22mm  Tube  at  9",  four  seconds  at 

Fig.  266  (right)  22mm  Tube  at 
11",  four  seconds  at  f:18 

The  high  magnification  that  can  be  obtained  by  the  use  of  extension 
tubes  is  shown  in  the  typodont  of  gold  foil  work  (figs.  269-271,  typodont  by 
Dr.  E.  D.  Shooshan,  Pasadena,  Calif.).  The  picture  of  the  gold  foils  in  the 
upper  right  first  molar,  the  single  tooth  and  the  typodont,  are  all  enlarged 
to  the  same  degree  from  their  original  pictures.  The  relative  enlarging  was 
done  in  the  photography  by  means  of  the  tubes,  and  not  in  the  printing. 

The  color  record  of  the  light  pink  of  condensite  material  is  shown  in 
this  typodont.  The  color  record  which  vulcanite  will  give  is  shown  in  figure 
262.  The  anterior  portion  was  gum  pink  and  the  posterior  portion  maroon. 
Figure  261  also  shows  maroon  vulcanite.  No  color  filters  were  used. 

Fig.  267     22mm  Tube  at  10",  four 
seconds  at  f  :18 

Fig.  268     22mm  Tube  at  12",  one 
second  at  f  :18 

In  the  photographing  of  small  inanimate  objects  I  prefer  the  soft  light 
of  daylight  rather  than  the  artificial  illumination  of  electricity.  Figures 
261,  263,  264,  266,  271,  269  and  270  were  all  made  without  artificial  illumina- 
tion. The  objects  were  placed  on  a  small  stand  close  to  one  window.  There 
was  one  other  window  in  the  room  which  was  used  to  help  modify  the 


Some  objects,  however,  require  stronger  highlights  and  shadows.  These 
can  be  illuminated  best  with  a  Photofiood  serving-  as  the  spotlight,  and  day- 
light providing  the  floodlight  Figures  262,  265  and  268  are  examples  of 
this  type.  The  lighting  of  figure  267  was  obtained  by  placing  .the  radio- 
graphic  film  on  a  radiographic  viewing  box. 

Fig.  269     12  and  22mm  Tubes  at 
S1^",  six  seconds  at  f  :18 

Fig.  270  9,0,  60,  22  and  12mm 
Tubes  at  12  W,  twelve  seconds  at 

r-m- ' 

Fig.  271  12mm  Tube 
at  9",  four  seconds  at 

Fig.  272  Record  stamp 

Fig.  273     Print  with 
record  on  back 

Importance  of  Keeping  Accurate  Records 

The  photographer,  who  is  interested  in  reproducing  rapidly  any  type 
of  scene  must  work  out  a  systematic  routine  based  on  accurate  records. 
This  is  particularly  true  of  photography  in  any  phase  of  science,  where 
close-up  apparatus  is  used  and  slight  variations  are  of  great  importance. 
Here  the  subject  is  frequently  a  patient  and  time  must  be  conserved  for  all 

Following  is  a  routine  which  will  permit  check-up  and  reference: 

1.  Prepare  a  pad  of  paper.     With  a  record  stamp   (fig.  272),  stamp  all 
sheets  on  the  pad. 

2.  Place  subjects  as  desired,  adjust  camera  and  lighting. 

3.  Use  Leicameter.   Determine  light  value  and  select  correct  aperture  and 
time.  ' 


Dental  Photography 

4.  Now STOP • and 


5.  If  planning  to  take  more  than  one  shot  of  this  subject  (possibly  experi- 
menting with  varying  apertures  and  timing)  record  (on  chart  fig.  273) 
EVERY  shot  in  that  series,  BEFORE  TAKING  A  SINGLE  PICTURE. 

6.  Then  photograph  AS  PLANNED. 

Following  the  development  of  the  film,  study  It  through  the  Leica  film 
viewer  and  marker.  By  means  of  this  device  clip  a  notch  on  the  border  of 
the  film  to  designate  each  picture  to  be  enlarged. 

Another  method  of  choosing  the  pictures  to  be  enlarged  is  to  make 
strip  prints  from  the  entire  film  and  then  make  your  selection.  If  you  use 
this  routine  be  sure  to  mark  the  small  prints  in  some  suitable  manner  and  in 
addition  return  to  the  film  and  clip  the  notches.  This  is  particularly  im- 
portant where  you  have  taken  a  number  of  test  exposures  of  the  same 

Numbers  are  to  be  found  marking  each  picture  on  some  brands  of 
film,  while  others  are  blank.  Those  that  are  blank  should  now  be  numbered 
on  the  film  in  ink  to  correspond  with  the  numbers  on  the  last  line  of  the 
record  chart.  Those  films  which  have  numbers  on  the  border,  will  seldom 
be  found  labeled  1-36,  but  are  more  apt  to  be  numbered  22-36,  1-21,  or  14-36, 
1-13,  etc.  Therefore,  these  numbers  which  appear  on  the  film  must  be  re- 
corded on  the  next  to  bottom  line  on  chart. 

When  an  enlargement  (fig.  273)  has  been  printed,  turn  it  over  and 
stamp  the  record  chart  on  its  back.  Then  fill  in  all  data  found  on  the 
original  chart  for  that  print.  Now  devise  some  filing  system.  For  mine 
I  have  chosen  to  paste  the  pictures  on  9"  x  12 "  sheets  of  heavy  paper  that 
come  in  an  I-P  class  G  T  sectional  post  binder,  top-locking  #7717.  I  have 
strip  prints  made  of  the  entire  film  and  paste  those  for  one  film  on  one 
sheet  of  paper.  For  quick  reference  I  now  write  the  numbers  on  the  strip 
prints,  and  it  is  at  this  point  that  I  mark  each  print  to  be  enlarged.  The 
papers  carrying  the  enlargements  have  the  record  chart  stamped  on  them 
and  filled  in  beneath  each  enlargement.  Any  enlargements  which  are  not 
mounted  are  stamped  as  shown  above  in  figure  273. 

It  seems  a  bit  safer  not  to  cut  the  negatives  but  to  store  them  in  the 
metal  film  box.  Here  they  are  ready  for  instant  use  by  referring  to  the 
strip  prints. 

The  result  of  the  above  will  be  a  systematic  record  of  all  factors  in- 
volved in  obtaining  every  photograph.  When  you  have  a  new  photograph  to 
take  you  can  very  readily  pick  out  from  your  file  the  print  most  closely 
resembling  it  and  proceed  by  duplicating  the  recorded  factors. 

Above  all,  remember  this.  Any  record  routine  that  is  developed 
along  systematic  lines  will  prove  invaluable  to  anyone  anxious  for 
scientific  results.  It  can  be  a  routine  very  different  from  the  above 
and  still  be  a  system.  It  is  not  important  to  copy  this  one,  which 
I  know  works  in  a  highly  satisfactory  manner  and  saves  time  and 
money.  It  is  important,  however,  to  develop  some  routine  which  is 
systematic,  accurate  and  complete. 


LEICA  photos  by 

Dr.  Ramon  Castroviejo 

Normal  Eye. 

50mm  Summar,  f:  1-2.5,  1/20  sec. 

Tumor  of  lower  Eye-lid. 

50mm  Elmar,  f:9,  1/8  sec,.  3cm 


Pig-mented  Condition  of  the  Eye. 
50mm  Elmar,  f:9,  1/8  sec.,  3cm 

Congenital  Coloboma  of  the  Iris. 

50mm  Elmar,  f  :9,  1/8  sec.,  3cm 


Dupont  Superior  film. 

Greater  Enlargement  of  No.  4. 



Photography  of  anterior  segments  of  the  human  eye  for  scientific 
and  medical  purposes  presents  problems  peculiarly  its  own.  A  photo- 
graphic camera  directed  at  an  eye  actually  faces  another  camera, 
and  a  well  designed  one  too,  to  say  the  least.  Besides  this  our  camera 
faces  one  of  the  most  sensitive  and  delicate  centers  of  the  nerve  sys 
tern,  a  very  delicate  and  accurate  optical  organ  and  a  convex  mirror, 
photographically  speaking:  a  wide-angle  reflecting  surface. 

To  produce  photographs  of  an  eye  one  needs  a  good  camera  with 
an  optical  system  as  flexible  as  possible.  One  needs  good  and  suit- 
able illumination  capable  of  delivering  the  light  required  for  short 
exposures  without  unnecessary  strain  to  the  eye.  One  needs  fast 
films  with  broad  latitude  of  emulsion  and  with  a  full  color  correction. 
And  plenty  of  patience  1 

If  it  is  difficult  to  make  precision  still  photographs  of  the  eye, 
it  is  harder  yet  to  take  motion  pictures  of  it.  This  is  particularly 
true  in  cases  where  the  eyes  to  be  photographed  are  diseased  or  abnor- 
mal, extremely  sensitive  to  light,  easily  irritated  by  prolonged  ex- 
posure to  air.  Such  eyes  are  usually  in  motion,  almost  constantly. 
But  even  if  it  were  possible  to  immobilize  them  for  a  moment  the  iris 
would  never  remain  stationary:  the  movement  of  this  remarkable 
living  diaphragm  cannot  be  controlled  at  will;  the  size  of  the  aper- 
ture, the  pupil,  is  constantly  changed  as  the  iris  contracts  or  dis- 
tends. Strong  light,  such  as  is  required  for  short  exposures  is  almost 
invariably  unbearable  to  the  eye,  causing  irritation  accompanied  by 
lacrimination,  nervous  movements  of  the  eye-ball,  eye-lids  and  the 
entire  head. 

During  a  recent  production  of  a  motion  picture  dealing  with 
subnormal  vision  and  describing  various  optical  devices,  spectacles 
and  other  aids  designed  to  overcome  this  handicap,  a  number  of 
" close-ups M  of  eyes  (anterior  segments)  were  required  to  show  the 
specific  condition  of  the  case  for  which  the  particular  type  of 
spectacle  was  being  designed.  The  motion  picture  was  to  amplify 
a  lecture  by  showing  and  explaining  visually  to  the  profession  the 
technique  of  examination  of  eyes  having  sub-normal  visual  acuity,  the 


optical  principles  underlying  the  construction  of  the  different  types 
of  telescopic  spectacles,  pin-hole  spectacles,  compound  magnifiers,  con- 
tact lenses,  etc.  The  various  deformities  and  anomalies  encountered 
in  cases  of  sub-normal  vision  had  to  be  shown  to  demonstrate  available 
methods  of  optical  treatments  of  the  different  types  of  defective 

It  was  felt  that  it  would  be  useless  to  expose  patients  to  the 
strain,  discomfort  and  hardships  of  motion  picture  photography  for 
close-ups  of  anterior  sections.  It  was  found  that  "stills"  of  these 
anterior  segments,  showing  the  affected  eyes  in  great  detail,  when 
rephotographed  on  motion  picture  film  yielded  all  that  was  desired 
and  even  more,  having  several  advantages.  Besides,  these  "stills7* 
were  usable  for  making  of  lantern  slides  and  also  for  case  history 

Fig.  275  Leica  mounted  on 
a  Simplex-Pockette  16mm 
motion  picture  camera  out- 
fit for  making  still  and  mo- 
tion pictures  at  the  same 
time.  The  author  assem- 
bled this  outfit  for  his 
medical  and  scientific  work 


Ophthalmic  Photography 

The  entire  picture  (some  1600  feet  of  16mm  film)  was  produced 
within  eight  weeks.  Two  Simplex-Pockette  cameras  were  used  in  the 
production.  Figure  275  shows  one  of  these  outfits  specially  adapted 
for  this  work.  The  Leica  camera  was  mounted  atop  the  motion 
picture  camera,  where  it  performed  double  duty:  it  was  used  to 
check  exposures  and  general  lighting  arrangement  of  each  set-up, 
and  to  produce  " stills"  of  every  scene  quickly,  stills  that  were  easily 
available,  easily  reproduced  and  enlarged  to  any  size  desired.  This 
outfit  was  used  for  the  general  work:  long  and  medium  shots.  For 
close-ups  of  anterior  segments,  requiring  utmost  precision,  another 
outfit  was  designed  and  assembled. 

Fig.  276     The  Leica  as  an 
Ophthalmic  camera 

The  Leica  Equipment 

A  Leica  was  mounted  upon  a  heavy  compound  base  of  a  binocular 
ophthalmic  microscope.  The  base,  equipped  with  cross-slide  adjust- 
able movement  was  particularly  well  adapted  as  a  support  for  the 
camera;  while  extremely  rigid  it  permitted  free  and  fully  controlled 
movement  of  the  camera  in  every  desired  direction  for  adjustment 
and  focusing.  Thus  mounted  upon  the  base  the  camera  was  placed 
on  a  heavy  adjustable  instrument  table  equipped  with  an  elevating 
gear  and  an  adjustable  head-and-chin  rest.  The  entire  outfit  was 
very  heavy  and  rigid,  permitting  accurate  and  dependable  control  of 
the  equipment  at  all  times  without  being  subject  to  vibrations.  The 
illustrations  show  the  arrangement  as  used  in  detail. 


The  outfit  was  assembled  from  the  following  units  and  parts : 
1.    Leica  Camera  Model  F.  2.    Lens  Shade. 

3.    Spirit  Level.  4.    Cable  Release. 

5.  Compound  Binocular  Microscope  Base. 

6.  Instrument  Table  with  Head   and   Chin  Rest. 
1.    Sliding  Focusing  Attachment  Model  No.  1, 

8.  Magnifier    with    adjustable    collar   for    above. 

9.  Special  Attachment  Ring  (ordinarily  used  on 
the  lens  when  used  in  the   Valoy   enlarger). 

Two  diagonal  hair-lines  were  etched  into  the  surface  of  the 
ground  glass  of  the  Focusing  Attachment  for  better  centering  of  the 
image.  Greater  brilliance  of  the  image  upon  the  ground  glass  was 
obtained  by  rubbing  in  a  drop  of  oil  into  the  ground  side  of  the  glass. 

The  magnifier  not  only  aided  materially  in  critical  focusing,  but 
also  acted  in  lieu  of  a  focusing  cloth,  keeping  out  extraneous  light 
during  focusing  on  the  ground  glass.  The  spirit  level  was  used  to 
obtain  better  alignment  of  the  camera  with  the  optical  axis  of  the 
eye  to  avoid  distortion.  The  special  attachment  ring  was  used  over 
the  lens  to  facilitate  the  operation  of  the  lens  diaphragm.  It  also 
served  admirably  as  a  lens  shade.  In  addition  to  the  above  the  fol- 
lowing color  filters  in  mounts  were  used :  Panchromatic  XI  and  X2? 
Yellow  No.  1  and  No.  2  and  Eed  (A). 

The  optical  equipment  consisted  of  the  standard  Elmar  50mm 
f  :3.5  lens  and  the  30mm  extension  tube.  It  was  found  that  this  lens 
has  excellent  sharpness,  correction,  definition  and  resolving  power. 
This  lens,  when  used  in  connection  with  the  30mm  extension  tube 
mounted  upon  the  Sliding  Focusing  Attachment  produced  images  of 
the  eye  upon  the  film  almost  normal  size.  When  set  for  infinity  with 
the  working  distance  from  the  eye  being  108  mm  the  exact  ratio  of 
the  size  of  the  object  to  the  size  of  the  image  of  film  is  1 :0.S2. 

The  Focusing  Attachment  with  the  camera  connected  to  it  was 
mounted  upon  the  compound  base  by  means  of  a  brass  key  which 
fitted  into  a  groove  in  the  head  of  the  base.  A  set  screw  tightened 
the  connection  rigidly.  This  arrangement  rendered  the  camera  out- 
fit easily  interchangeable  with  the  microscope,  thus  permitting  the 
use  of  either  at  will.  It  also  assured  utmost  rigidity  and  freedom 
from  play  and  vibration,  the  importance  of  which  cannot  be  over- 

The  outfit  having  been  assembled,  considerable  experimental  work 
preceded  the  actual  taking  of  pictures  of  cases.  The  entire  procedure 
of  photographing  anterior  segments  had  to  be  standardized  and 


Ophthalmic  Photography 

simplified  before  patients  were  requested  to  sit  before  the  camera. 
Correct  exposures,  arrangement  of  lights,  type  of  film,  filters  and 
many  other  details  had  to  be  worked  out  and  definitely  established. 

Correct  exposures  were  determined  with  the  Weston  Photo- 
electric Leicameter.  Factors  of  film,  filters,  and  extension  tubes  be- 
ing known,  it  was  a  simple  matter  to  arrive  at  the  correct  timing  of 
the  shutter.  The  factor  of  the  30  mm  tube  with  the  lens  set  at 
infinity  is  2.2  x.  The  lens  was  usually  stopped  down  to  f  :9  or  f  :12.5. 
Such  small  apertures  were  required  to  obtain  greater  depth  of  focus. 
Good  definition  was  obtainable  at  these  apertures  of  all  parts  of  the 
eye,  including  edges  of  eye-lids,  corners  of  eye.  The  maze  of  capillary 
blood  vessels  of  the  selera  (white,  opaque  portion  of  the  eye-ball)  was 
also  always  in  sharp  focus.  This  depth  of  focus,  though  not  essential 
to  the  picture,  imparted  usually  a  feeling  of  roundness  and  depth, 
with  resulting  life-like  appearance  of  the  eye. 

The  success  of  the  work  depended  not  only  upon  a  standardized  pro- 
cedure of  the  technique  of  photography,  but  also  on  uniformity  of  materials, 
processing  and  laboratory  work.  For  film  the  Du  Pont  Superior  Panchro- 
matic was  selected  because  of  its  latitude  of  emulsion,  speed  under  artificial 
light,  its  color  correction,  response  to  filters  and  its  grain  structure.  All 
film  was  developed,  hardened,  fixed  and  washed  in  Correx  tanks.  For  de- 
veloper the  well-known  Du  Pont  fine-grain  formula  was  selected:  it  yielded 
fine  grain  with  minimum  loss  of  speed  and  definition;  this  formula  is  known 
as  Dr.  Sease  No.  3.  (See  chapter  on  Film-Development.) 

The  use  of  color  filters  was  avoided  as  much  as  possible.  Only 
where  it  was  absolutely  necessary  were  they  put  into  service.  Par- 
ticularly, where  special  colors  required  it  for  the  purpose  of  correct 
monochromatic  rendering  the  color  filters  were  resorted  to.  An 
example  of  this  is  offered  in  figure  277. 

fl  Fig.  277    Congenital 

Elmar  50mm  lens,  30mm 
Tube.  Photoflash  exposure 
at  f:12.5.  DuPont  Supe- 
rior film.  Red  (A)  filter 


This  photograph  showing  a  case  of  a  congenital  coloboma  of  an  eye 
was  made  with  the  Wratten  (A)  Eed  filter  to  separate  the  dark  brown 
iris  from  the  black  pupil.  The  same  photograph  made  without  this 
filter  showed  no  appreciable  difference  between  these  two  colors. 

Importance  of  Focusing 

Focusing  of  the  image  on  ground  glass  was  usually  done  with 
the  lens  wide  open.  Subsequently  it  was  stopped  down  to  the  desired 
aperture.  For  this  work  the  special  Attachment  Eing  placed  on  the 
front  of  the  lens  was  almost  invaluable.  With  the  eye  only  4-5 
inches  away  from  the  lens,  it  would  have  be-en  difficult  to  reset  the 
lens  diaphragm  to  the  desired  stop  without  disturbing  the  patient. 
This  ring  has  outside  calibrations,  which  though  not  in  *kf';  values 
are  easily  memorized  as  to  their  equivalents.  The  patient  was  placed 

Fig.  278  Attachment  Eing,  which  is  extremely  use- 
ful for  adjustment  of  lens  diaphragm  (Elmar  or 
Hektor  50mm)  in  close-up  work.  It  acts  also  as  a 
lens  shade 

comfortably  in  the  chair,  the  table  raised  to  a  level  where  the  lens 
of  the  camera  was  opposite  the  eyes,  and  then  the  vertical  and  hori- 
zontal fine  adjustments  were  made  by  means  of  the  rack-and-pinion 
of  the  cross-slide  movement  of  the  base.  The  head  of  the  patient  was 
made  to  rest  upon  the  chin  rest,  after  which  the  focusing  was  made, 
the  lights  turned  on  and  the  exposure  quickly  made. 

Illuminating  the  Eye 

Which  brings  us  to  the  most  trying  and  difficult  problem  of 
photographing  the  eye:  the  illumination.  The  eye  acts  as  a  wide- 
angle  mirror-like  reflecting  surface  (convex).  Not  only  will  it  reflect 
the  light  source,  but,  under  certain  conditions,  the  camera  and  its 
operator  as  well.  Photographs  of  the  eye,  therefore,  should  be  made 
in  a  room  free  from  illuminated  objects  or  light  sources  other  than 
those  used  for  the  direct  illumination  of  the  eye.  There  should  be 
no  light  entering  through  the  windows,  no  skylights,  nor  ceiling 
lights.  Lights  used  for  illumination  should  be  placed  as  far  as  pos- 
sible from  the  eye  to  render  their  reflections  small  and  inconspicuous. 
Total  lack  of  reflection  in  the  eye  is  not  desirable,  because  these  re- 
flections lend  the  picture  of  the  eye  that  spark  of  life,  that  roundness 
and  fulness  which  distinguishes  it  from  a  dead  eye. 

It  is  difficult  to  illuminate  a  normal  eye  sufficiently  for  an  in- 
stantaneous exposure  of  a  small  lens  aperture.  Prolonged  exposures 


Ophthalmic  Photography 

are  undesirable  because  of  the  ever-present  possibility  of  movement 
of  the  eye.  But  there  are  abnormal,  diseased  eyes,  with  all  kinds  of 
lenticular,  retinal,  corneal  involvements,  which  actually  abhor  light. 
There  are  cases  of  Photophobia  (which  does  not  mean  that  they  abhor 
photographers,  although  they  actually  do!);  light,  even  daylight, 
hurts  them.  Their  eyes  must  be  shielded,  protected  from  light,  and 
not  exposed  to  it. 

Thus,  although  the  entire  process  of  photographing  anterior  seg- 
ments was  standardized  sufficiently  to  form  a  kind  of  routine,  the 
matter  of  handling,  selecting  and  arranging  lights  had  to  be  treated 
differently  in  each  and  every  individual  case.  It  had  to  be  made  to 
suit  not  only  every  patient,  but  the  condition  of  each  eye  as  well; 
for  there  were  cases  where  one  eye  was  entirely  different  from  the 
other.  Before  the  patient  was  placed  before  the  camera,  the  reaction 
of  his  eyes  to  light  had  to  be  definitely  and  carefully  determined  by 
the  doctor. 

Flashlight  Eye  Exposures 

In  the  case  of  eyes  particularly  sensitive  to  light,  the  most  satis- 
factory method  of  illumination  was  found  in  the  Photoflash  bulb. 
The  bulb  was  usually  placed  in  the  reflector  of  a  goose-neck  type  floor 
lamp.  A  diffusion  screen  was  placed  before  the  photoflash  bulb;  not 
so  much  because  of  the  intensity  of  the  light,  but  because  these  bulbs 
occasionally  crack  or  break  when  flashed.  The  tiny,  thin  fragments 
of  glass  would  be  dangerous  to  the  eye  of  the  patient,  and  one  cannot 
be  too  careful  in  protecting  it.  The  reflector  was  usually  placed  some 
five  to  six  feet  away  from  the  eye,  slightly  above  its  level  and  to  one 
side  of  it.  On  the  other  side  of  the  eye  a  white  reflecting  surface  was 
placed  to  provide  even  illumination,  thus  imparting  roundness  to  the 
picture.  Actual  focusing  was  done  with  the  light  of  a  15-watt  bulb, 
placed  conveniently  near  the  camera.  The  shutter  of  the  camera  was 
synchronized  with  the  switch  of  the  bulb;  and  at  the  moment  sharp 
focus  was  obtained,  the  exposure  was  made. 

In  most  instances  the  patient  was  barely  aware  of  an  intense 
light  sensation  in  connection  with  the  flash,  which  lasts  only  about 
l/50th  to  l/75th  of  a  second — too  short  to  register  any  intensity  upon 
the  retina  of  the  eye.  To  be  sure  of  critical  focus,  it  was  at  times 
necessary  to  use  a  special  head-and-chin  rest  for  the  patient.  The  rest 
was  provided  with  a  small  piece  of  flat  wood,  attached  crosswise. 
The  patient  was  askod  to  hold  the  wood  firmly  between  his  teeth  dur- 
ing focusing,  retaining  the  assumed  position  for  the  exposure. 


Ophthalmic  Photography 

Eyes  with,  normal  reaction  to  light  were  photographed  with  the 
aid  of  two  500-watt  bulbs,  or  two  Photoflood  bulbs,  in  suitable  re- 
flectors with  tracing  cloth  diff users.  The  reflectors  should  not  be  of 
the  polished  type,  but  of  the  oxidized,  dull,  aluminum  finish,  to  avoid 
reflections  of  filaments  upon  the  subject.  One  light  was  placed  on 
each  side  of  the  eye;  one  closer  to  it  (four  to  five  feet),  the  other 
farther  away  (six  to  eight  feet).  The  farther  the  light  source  from 
the  eye  the  smaller  its  reflection  in  the  eye.  Frequently  a  white 
reflecting  surface  placed  on  one  side  of  the  eye  replaced  the  second 
light,  but  at  some  increase  in  exposure.  Focusing  was  again  done 
with  the  light  of  a  low  wattage  bulb  conveniently  placed  near  the 
camera  and  near  to  the  patient's  eye. 

"Fig.  280  Dr.  R.  Castroviejo  using  the  Leica  for  photography 
of  anterior  segments  of  the  eye.  Adequate  illumination  is  se- 
cured by  means  of  head  mirror  reflecting  powerful  spotlight 
at  time  of  exposure 

Leica  for  Clinical  Photography 

I  am  indebted  to  Dr.  Ramon  Castroviejo  of  the  Opthalmic 
Institute,  Columbia-Presbyterian.  Medical  Center,  New  York,  for 
extremely  valuable  information  and  ingenious  methods  of  illumina- 
tion of  anterior  segments  of  the  eye.  Dr.  Castroviejo  assembled 
independently  a  Leica  outfit  for  this  work,  quite  similar  to  the  one 
described  here,  with  which  he  -obtains  some  remarkable  photographs 
of  anterior  segments.  He  was  good  enough  to  demonstrate  some 
of  his  work  and  to  permit  me  to  use  some  of  his  Leica  pictures, 


which  are  shown  here.  Dr.  Castro viejo's  work  is  remarkably  well 
illustrated  with  Leica  photographs,  only  some  of  which  can  be 
shown  here. 

Dr.  Castroviejo  uses  his  Leica  outfit  as  an  Opthalmic  camera 
extensively  in  his  clinical  work  The  results  of  his  surgical  and 
therapeutic  treatments  of  eyes  are  constantly  and  periodically 
recorded  photographically,  furnishing  a  most  detailed  visual  record 
for  his  case  histories.  Many  photographs  thus  obtained  are  subse- 
quently made  into  lantern  slides,  and  used  in  lectures. 

Illustrations  which  follow  show  the  ingenious  illumination 
methods  used  by  Dr.  Castroviejo. 

In  setting  up  and  operating  the  Leica  Opthalmic  equipment  Dr. 
Castroviejo  proceeds  as  follows: 

1.  A  standard  surgical  spot-light  equipped  with  a  500-Watt  bulb 
and  a  water  filter  as  well  as  a  system  of  condensing  lenses  for 
focusing  and  narrowing  the  beam  of  light  is  placed  alongside  the 

2.  The  beam  of  light  is  directed  at  the  head  of  the  person  operating 
the  camera. 

3.  The  operator  wears  a  head-mirror  of  the  kind  used  by  nose  and 
throat  specialists  during  examination  of  interior  organs.     The 
beam  of  light  from  the  spot-light  strikes  the  mirror  and  is  re- 
flected by  it  in  any  direction  desired. 

4.  By  means  of  slight  movements  of  the  head  the  operator  is  in  a 
position  to  direct  the  beam  of  light  upon  the  eye  to  be  photo- 
graphed for  as  short  or  as  long  a  time  as  indicated. 

5.  The  camera  is  focused  as  usual,  the  operator  standing  behind  it 
opens  the  camera  shutter  and  at  the  same  time  by  a  mere  nod  of 
his  head  makes  the  beam  of  light  pass  quickly  across  the  eye. 

6.  Directly  afterwards  the  shutter  is  closed. 

7.  With  a  little  practice  remarkable  ease  is  acquired  producing  ex- 
cellent results  with  minimum  discomfort  to  the  patient.    The  beam 
of  light  need  remain  upon  the  eye  a  mere  fraction  of  a  second. 

Another  method  used  by  Dr.  Castroviejo  consists  of  placing  the 
same  spot-light  opposite  the  patient's  eye,  alongside  the  camera,  with 
the  beam  directed  at  the  eye.  In  this  case  use  is  made  of  the  compur 
shutter  with  which  the  spot-light  is  equipped,  controlled  by  a  cable 
release.  The  shutter  has  speeds  of  1/25  to  1/50  of  a  second.  After 


Ophthalmic  Photography 

focusing  the  camera  with  the  aid  of  a  low-wattage  bulb,  the  spot- 
light is  turned  on  with  the  compur  shutter  remaining  closed,  but  set. 
for  the  desired  speed.  Opening  the  shutter  of  the  camera,  releasing 
the  shutter  of  the  spot-light,  and  closing  the  shutter  of  the  camera, 
takes  less  time  than  to  say  it !  The  illustrations  show  details  of  these 
various  set-ups. 

Use  of  the  Placido  Disc 

Several  photographs  were  required  of  eyes  with  deformities  of 
the  cornea.  The  cornea  (the  outer  transparent  part  of  the  eye-ball; 
of  a  normal  eye  is  spherical,  forming  a  segment  of  a  sphere  slightly 
smaller  in  diameter  than  that  of  the  eye-ball  itself.  It  is  smooth  and 
glossy.  Its  roundness  and  smoothness  enable  it  to  act  as  a  convex 
reflecting  surface.  In  some  cases  the  cornea  assumes  shapes  different 
from  normal,  sometimes  resembling  a  cone,  in  other  cases  it  develops 
deformities  of  the  outer  surface,  irregularities  of  the  curvature, 
wrinkles,  etc.  All  of  these  deformities  result  in  distorted  and  defec- 
tive vision.  Some  of  them  are  very  slight,  however,  barely  visible  to 
the  eye.  The  fact  that  a  normal  cornea  acts  as  a  convex  mirror  had 
been  utilized  in  the  detection  of  these  irregularities  and  in  their 
accurate  measurement.  A  white  disc  (known  as  the  Placido  Disc), 
some  12  to  18  inches  in  diameter,  upon  which  had  been  drawn  con- 
centric black  circles  about  1  inch  wide  and  about  1  inch  apart,  is 
placed  in  front  of  the  eye.  Through  an  aperture  in  the  center  of  the 
disc  one  can  observe  the  reflection  of  this  disc  in  the  eye.  A  normal 
cornea  will  reflect  a  true  reduced  image  of  these  concentric  black  and 
white  circles,  fully  retaining  their  roundness,  spacing  and  concen- 
tricity. A  malformed  cornea  will  reflect  a  distorted  image,  from  the 
nature,  shape  and  direction  of  which  the  character  of  the  malforma- 
tion can  be  diagnosed  and  measured. 

Fig.  281     Placido  Disk  Reflection  in  Cornea  Fig.  282     Placido  Disk  Reflection  in  Cornea 

of  Normal  Eye  of   Diseased   Eye 


To  obtain  photographs  of  reflections  of  Placido  Discs  in  normal 
and  in  abnormal  eyes  the  same  Leica  outfit  was  used,  but  the  illumina- 
tion was  changed.  A  Placido  Disc  was  placed  over  the  lens,  which 
was  accomplished  by  inserting  into  its  center  aperture  a  black  paper 
tube  (about  2"  long),  which  in  turn  was  slipped  over  the  Leica  lens. 
The  black  paper  tube  acted  as  an  extended  lens  hood.  The  center  of 
the  Placido  Disc  was  made  to  coincide  approximately  with  the  optical 
axis  of  the  lens.  Two  500-watt  bulbs  in  reflectors  were  placed  slightly 
behind  the  patient  and  the  light  was  directed  at  the  Placido  Disc. 
The  light  reflected  from  the  white  portions  of  the  disc  served  to 
illuminate  the  eye.  In  arranging  the  lights  care  was  taken  to  prevent 
direct  rays  of  light  from  striking  the  elements  of  the  lens.  The  fol- 
lowing illustrations  show  a  photbigiraph  of  a  normal  eye  and  that  of 
an  eye  with  a  distorted,  malformed  cornea. 

Portraits  of  Patients 

The  flexibility  of  this  Leica  outfit  made  it  possible  to  use  it  for  still 
another  purpose.    By  simply  removing  the  30mm  extension  tube  and  mount- 
ing the  50mm  lens  directly  upon  the  sliding  focusing  attachment  one  se- 
cured a  portrait  view  camera  with  a  ground  glass  upon  which  to  compose 
the  picture.    Focusing-  in  this  case  was  accomplished  by  unlocking  the  lens 
barrel  of  the  Elmar  50mm  lens  (turning  it  counter-clockwise)  and  moving 
it  in  and  out.  Portraits  of  patients  were  wanted  for  case 
histories  and  records  to   show  the  marked   difference 
in  facial  expressions  resulting  from  improved  vision. 
The  tired,  haggard  and  tense  expression  typical  of  a 
patient  during  his  early  examinations  was  usually  su- 
perseded by  an  expression   of  ease   and   contentment 
after  the  correct  spectacles  were  fitted.    For  this  pur- 
pose photographs   of  the  head  and   a   portion   of   the 
shoulders  were  wa'nted.     Fo.r  photographs  of  anterior 
segments   the  patient  was  asked  to  lean  forward   in 
his  chair  and' to  rest  his  head  upon  the  chin  rest.    For 
portraits  the  same  patient  was  asked  to  lean  upon  the 
back  of  the  chair.     The  change  in  the  focal  length  of 
the   lens,  produced  .by  the  removal   of  the   extension 
to^ra2!3  ?fcorp5h°"   tube>   permitted   making   these   two   different  pictures 
w!anpng  Pin-hofe 1<m    without  moving  the  camera,  nor  for  that  matter  dis- 
Spectacies  turbing  the  patient,  who  did  not  have  to  leave  the  chair. 

Subsequently  a  system  of  records  .of  cases  was  developed  consisting  of 
mounting  on  the  back  of  history  cards  pictures  showing  the  patient  at  first 
examination,  anterior  segments  of  his  eyes,  and  a  photograph  of  the 
patient  wearing  spectacles  designed  for  him.  A  photograph  of  such  a 
portrait  is  shown  here. 

The  usefulness  of  this  Leica  outfit  did  not  stop  after  the  comple- 
tion of  photographs  of  anterior  segments  and  portraits  of  patients. 
Another  phase  of  the  motion  picture  work  offered  great  difficulties 


Ophthalmic  Photography 

and  again  the  Leica  was  put  to  work  and  successfully  used  as  a  short- 
cut. In  explaining  the  principles  underlying  the  construction  and 
design  of  various  spectacles  used  as  aids  to  eyes  affected  with  sub- 
normal vision  it  was  desired  to  show  how  a  beam  of  light  is  refracted 
in  passing  through  the  medium  of  a  lens,  what  happens  to  it  when  it 
enters  the  eye,  and  how  the  path  of  this  beam  of  light  can  be  con- 
trolled to  produce  an  image  upon  the  retina  by  making  it  pass  through 
certain  media  before  entering  the  eye. 

Smoke  Box  Photography 

A  schematic  model  of  the  eye  was  built  of  glass.  Also  a  special 
"smoke  box",  consisting  of  a  wooden  box,  painted  with  dead  black 
coating  inside.  One  of  the  sides  of  the  box  was  fitted  with  plate  glass, 
which  enabled  observation  from  the  outside.  At  one  of  the  ends  an 
opening  was  made  through  which  a,  beam  of  light  could  be  admitted. 
An  optical  bench  was  placed  inside  the  box,  and  various  lenses,  slits, 
prisms,  pin-holes  and  similar  media  were  mounted  upon  it  aligned 
along  the  same  optical  axis.  A  strong  source  of  light-was  placed  on 
the  outside  of  the  box  with  the  beam  light  entering  the  box  through 
the  side  opening.  The  bunch  of  rays  entering  the  box  was  made  as 
nearly  parallel  as  possible.  When  the  box  was  filled  with  smoke  the 
path  of  rays  became  plainly  visible  in  a  darkened  room.  The  rays 
were  made  to  pass  through  lenses,  prisms,  slits,  pin-holes,  etc.,  and  as 
a  result  were  made  to  converge,  diverge,  change  direction,  intensity, 
etc.  At  the  end  of  considerable  experimentation  to  produce  the  de- 
sired results  this  turned  out  to  be  an  interesting  and  quite  a  dramatic 
spectacle.  But  the  motion  picture  camera  was  blind  to  it,  despite  fast 
lenses  and  fast  films!  Although  a  very  strong  source  of  light  was 

Fig,  284     Smoke  Box  photograph  showing  behavior  of  bundle  of  rays 
after  passing  through  convex  lens 

Elmar  50mm  lens.     Three  •  minutes  '  at   f:18.      DuPont   Superior   film.      Bed    (A)    filter 


used,  its  actinic  value  was  slight.  Because  what  we  saw  was,  of  course, 
not  light  itself,  but  merely  the  illuminated  minute  particles  of  smoke, 
which  reflected  less  light  the  farther  away  they  were  from  its  source. 
To  intensify  these  illuminated  particles,  a  bit  of  powdered  chalk  was 
shaken  into  the  smoke  box  just  before  the  exposure  was  made. 

The  Leica  was  used  to  record  these  set-ups.  When  enlarged  these 
photographs  were  rephotographed  on  motion  picture  film,  producing 
results  which  were  found  to  be  excellent  in  every  way.  The  camera 
mounted  upon  its  rigid  support  described  previously  was  as  free  from 
vibration  as  possible.  This  was  important  because  very  long  expos- 
ures were  required :  with  the  lens  stopped  down  to  f  :18  and  with  a 
red  (A)  filter  used  to  retard  the  light  and  to  bring  out  some  detail 
in  the  shadows  of  the  set-up  and  equipment  inside  the  smoke-box — 
the  exposures  ranged  from  2  to  5  minutes !  The  following  illustrations 
show  these  actual  photographs/obtained  in  this  manner  and  subse- 
quently incorporated  into  the  motion  picture  film. 

Fig.  285     Smoke  Box  photograph 

showing  behavior  of  bundle  of  rays  after  passing  through   simple   "telescope",    entering 
model  of  eye  and  forming  image  upon  retina.     Exposure  as  in  Fig.  284 

These  photographs  had  to  be  produced  in  a  darkened  room.  All 
those  present  in  the  room  had  to  remain  motionless  throughout  the 
long  exposures.  To  prevent  vibration  caused  by  street  traffic  and 
subways  the  actual  exposures  were  made  between  2  A.  M.  and  5  A.  M. 

When  reproductions  of  these  photographs  were  later  flashed  upon 
a  screen  as  a  part  of  the  motion  picture  they  appeared  just  as  real  as 
if  they  were  produced  directly  upon  the  moving  film,  there  being  no 
action,  but  merely  an  even  and  steady  flow  of  light,  i  Thus  these  stills 
were  just  as  effective,  but  much,  much  simpler  to  make  than  by  means 
of  a  " stop-mo tion"  mechanism  on  the  motion  picture  camera.  Gor- 


Ophthalmic  Photography 

rect  exposures  for  these  photographs  were  obtained  by  the  tedious, 
But  infallible  method  of  trial-and-error.  Exposures  varied  with  every 
set-up  because  of  various  light  intensities  resulting  from  the  use  of 
various  media  through  which  the  light  was  made  to  pass.  The  prepa- 
ration of  each  set-up  was  so  tedious  that  some  three  to  six  shots  of 
each  were  made :  just  to  play  safe. 

Fig.  286     Smoke  Box  photograph 

showing-  bundle   of   rays   entering  model   of  eye   rendered   defective  by    simulated    corneal 
opacities.     No  image  formed  upon  retina.     Exposure  as  in  Fig.   2$4 

At  the  conclusion  of  this  work  literally  hundreds  of  feet  of  Leica 
film  were  on  hand.  These  were  scrutinized  carefully,  the  best  ones 
chosen,  classified,  viewed  through  the  enlarger.  Test  prints  were 
made,  and  unessential  portions  of  photographs  masked  out. 

Glossy  5x7  prints,  f errotyped,  were  made  of  all  photographs 
desired  for  the  motion  picture  work.  They  were  uniform  in  size, 
finish,  all  were  arranged  and  centered  correctly.  Mounted  upon  a 
special  easel  these  prints  were  photographed  with  the  Simplex  Pock- 
ette  camera  in  such  a  way  that  the  white  borders  did  not  show. 

"When  these  " stills"  were  subsequently  projected  on  a  7  x  9  foot 
screen  they  appeared  amazingly  life-like,  brilliant  and  possessing  all 
the  roundness  and  detail  that  could  be  desired.  What  is  more,  as  far 
as  showing  anterior  segments  was  concerned,  these  stills  had  many 
advantages  over  actual  direct  shots :  each  eye  stood  still,  as  if  caught 
and  stopped;  it  was  wide  open  for  leisurely  examination  and  observa- 
tion of  its  defects  and  details.  There  was  no  contraction  of  the  iris, 
no  movement  of  eye-lids  to  obscure  portions  of  the  eye-ball,  there  was 
no  visible  trace  of  effort  on  the  part  of  the  patient  to  show  it,  no 
lacrimation  nor  discoloration,  which  usually  are  caused  by  prolonged 
examination  of  the  eye. 


Lightning  Striking  Empire  State 

John  P.  Gaty 

Ehnar  90mm  lens,  Time  Exposure  at  f  :4,  DuPont  Infra-D  film,  Wratten  C  and  F  filters 



Photography  by  means  of  light  beyond  the  ends  of  the  visible 
spectrum  offers  many  interesting  possibilities  to  the  experimenter. 
Ultra-violet  photography,  using  shorter  wave  lengths  than  those  trans- 
mitted by  optical  glass,  requires  expensive  quartz  lenses  and  filters 
which  are  not  available  to  the  average  photographer.  The  invisible 
light  of  the  extreme  red  and  infra-red  region,  which  consists  of 
longer  wave  lengths  than  the  visible  red  light,  can  be  utilized  for 
photography  without  the  aid  of  expensive  auxiliary  equipment.  A 
minimum  investment  in  this  type  of  experiment  would  be  the  pur- 
chase of  a  roll  of  infra-red  sensitive  film  and  a  red  gelatine  filter. 
The  ordinary  Leica  lens  of  any  type  will  work  perfectly,  although  the 
Elmar  series  should  be  set  at  a  scale  reading  of  100  feet  in  order  to 
focus  the  infra-red  rays  from  distant  objects.  The  Hektor  series 
requires  slightly  less  compensation,  while  the  latest  Summar  lens  is 
provided  with  a  special  index  mark  on  the  mount  for  the  purpose 
of  focusing  with  infra-red. 

If  close-ups  are  required,  adjust  the  lens  to  the  true  distance 
and  then  subtract  the  same  amount  of  angular  rotation  as  was  re- 
quired to  move  the  lens  from  the  true  infinity  position  to  the  selected 
infra-red  infinity  position.  This  amount  of  angular  rotation  is 
measured  on  the  circular  edge  of  the  focusing  ring.  In  all  cases 
the  infra-red  scale-reading  will  be  less  than  the  panchromatic  scale- 
reading,  by  a  very  slight  amount.  Images  formed  by  infra-red  rays 
focus  slightly  further  back  of  the  focal  plane  formed  by  visible  light. 
To  compensate  for  this  generally  slight  difference,  the  lens  should  be 
racked  out  by  something  like  1/200  of  its  focal  length.  Thus,  if  a 
50mm  lens  is  used  for  infra-red  photography,  it  should  be  racked 
out  about  %mm.  In  most  eases  the  correction  for  close-ups  is  un- 
necessary, due  to  the  depth  of  focus  of  the  lens. 

It  is  rather  difficult  to  visualize  the  nature  of  infra-red  rays.  The 
fact  that  the  word  red  is  made  part  of  its  name  should  not  be  taken 
to  imply  that  these  rays  are  colored  red.  The  name  of  these  rays 
implies  merely  that  they  can  be  located  in  the  spectroscope  in  the 


region  adjoining  red.  Because  the  human  eye  is  not  sensitive  to 
infra-red  rays  it  should  not  be  even  taken  as  light.  They  can  be 
most  accurately  described  as  invisible  rays.  It  is  quite  possible  to 
describe  infra-red  rays  as  heat  rays. 

The  use  of  infra-red  light  for  photography  is  not  new.  Almost 
one  hundred  years  ago  Herschel  made  infra-red  photographs  by  in- 
direct methods  which  are  still  used  to  explore  the  infra-red  regions 
beyond  the  range  of  response  of  our  most  modern  emulsions.  Hersehel 
discovered  that  an  emulsion  which  has  been  exposed  to  blue  light 
will  show  a  diminution  of  exposure  wherever  it  is  exposed  to  red 
or  infra-red  rays.  A  film  which  has  been  uniformly  fogged  by  blue 
light  will  then  show  a  positive  image  of  a  subsequently  made  infra- 
red exposure,  when  it  is  developed.  Patience  and  careful  control 
are  required  to  make  this  system  work  effectively,  but  it  offers  great 
possibilities  for  research  in  regions  otherwise  beyond  the  reach  of 

Infra-Red  Films 

Modern  infra-red  photography  dates  from  about  1910  when  the 
experiments  of  Professor  E.  W.  Wood  were  announced  to  world 
famous  scientific  organizations.  For  a  time  popular  interest  lagged, 
due  to  the  difficulty  of  obtaining  suitable  emulsions.  Recently,  great 
progress  toward  perfection  of  infra-red  sensitive  materials  has 
brought  the  amateur  photographer  stable  and  fairly  sensitive  emul- 
sions suitable  for  the  purpose.  Those  available  for  the  Leica  are 
Agfa  R  film,  DuPont  Infra-D  film  and  Eastman  K  film.  The  DTI- 
Pont  Infra-D  and  the  Agfa  E  films  are  especially  spooled  for  the 
Leica  and  are  available  from  all  dealers. 

It  is  extremely  important  to  use,  whenever  possible,  extremely 
fresh  material  that  is  sensitized  to  infra-red  light.  Fresh  films  will 
be  found  more  sensitive  than  old.  It  loses  its  sensitivity  in  a  com- 
paratively short  time.  Infra-red  film  six  months  old  is  generally 
half  of  its  original  speed  at  the  time  of  production.  It  is  therefore 
recommended  that  infra-red  film  be  secured  with  an  indication  as 
to  when  it  was  produced  at  the  factory. 

The  special  applications  of  infra-red  photography  depend  on 
two  main  characteristics  of  infra-red  light.  First:  it  has  unusual 
power  of  penetration  of  atmospheric  haze  and  certain  materials 
which  are  opaque  to  visible  light.  Second:  many  substances  show  a 
reflective  power  to  infra-red  light  which  has  no  apparent  relation 
to  their  reflective  power  to  visible  light.  The  full  range  of  wave 
lengths  of  infra-red  light  is  considered  to  be  about  three  thousand 



times  as  great  as  the  full  range  of  the  total  visible  spectrum  from 
violet  to  deep  red.  In  other  words,  if  the  total  visible  color  spectrum 
were  considered  as  a  piano  keyboard,  with  each  note  representing 
a  different  wavelength  band,  or  color,  it  would  take  a  piano  with 
three  thousand  progressively  arranged  keyboards  to  contain  all  the 
notes  or  colors  in  the  infra-red  spectrum.  Photographically,  only 
the  very  beginning  of  this  composite  keyboard  has  been  explored  to 
date,  since  most  experimenters  have  failed  to  reach  further  than  the 
top  of  the  fourth  standard  keyboard  length  above  the  visible  spec- 
trum. The  films  already  listed  reach  approximately  to  the  top  of  the 
first  standard  keyboard  length  above  the  end  of  the  visible  spectrum, 
but  in  this  region  alone  there  lies  a  complete  gamut  of  invisible  colors 
(if  such  a  thing  can  be) .  Since  these  cannot  be  seen,  their  effect  on 
the  infra-red  sensitive  film  must  be  determined  by  experiment. 

For  illustration:  some  black,  green,  olive,  blue,  and  violet  dyes 
will  photograph  as  light  gray  or  almost  white  under  certain  wave- 
lengths of  infra-red  light.  Other  dyes  matching  exactly  in  visible 
color  will  photograph  by  the  same  light  as  dead  black  or  dark  gray. 
This  fact  may  lead  to  adoption  of  specialized  infra-red  and  heat  re- 
fleeting  dyes  for  summer  clothing.  The  cloth  would  appear  to  be 
dark  to  the  eye  and  would  not  soil  readily,  but  would  be  as  cool  to 
wear  as  a  white  garment. 

Differences  in.  Infra-Red  Values 

These  two  fundamental  characteristics  of  atmospheric  penetra-